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Catalytic Methods for Aromatic C–H Amination: An Ideal Strategy for Nitrogen-Based Functional Molecules Jiao Jiao, Kei Murakami, and Kenichiro Itami ACS Catal., Just Accepted Manuscript • DOI: 10.1021/acscatal.5b02417 • Publication Date (Web): 07 Dec 2015 Downloaded from http://pubs.acs.org on December 12, 2015

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ACS Catalysis

Catalytic Methods for Aromatic C–H Amination: An Ideal Strategy for Nitrogen-Based Functional Molecules Jiao Jiao,† Kei Murakami,† Kenichiro Itami*†,‡ †

Institute of Transformative Bio-Molecules (WPI-ITbM) and Graduate School of Science,

Nagoya University, Chikusa, Nagoya 464-8602, Japan ‡

JST, ERATO, Itami Molecular Nanocarbon Project, Nagoya University, Chikusa, Nagoya 464-

8602, Japan

ABSTRACT. Transformations of aromatic compounds into the corresponding amines, amides, and imides through carbon–hydrogen (C–H) bond functionalization represent one of the most step- and atom-economical methods for the synthesis of arylamine compounds. Since arylamines are privileged structures in materials- and biology-oriented functional molecules, the development of novel and efficient synthetic methods for aromatic C–H amination has received significant attention from a wide range of research fields including materials and pharmaceuticals. This review covers recent advances in catalytic aromatic C–H amination reactions. An array of recently developed new reactions are categorized by the nature of aromatic substrates: (1) 5-membered heteroarenes, (2) arenes having a nitrogen moiety in the molecule

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(intramolecular C–H amination), (3) arenes having a directing group, (4) simple arenes with excess amounts, and (5) simple arenes as the limiting reagents.

KEYWORDS. direct aromatic C–H transformation, amination, amidation, imidation

TOC graphics

H funct-Ar

NR2

Catalytic aromatic C–H amination

funct-Ar


2

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Introduction Arylamines are ubiquitous in a range of biology-oriented aromatics1-3 and materialsoriented aromatics (Figure 1).4 Therefore, the development of efficient and step-economical methods for constructing aromatic carbon–nitrogen (C–N) bonds has been recognized as one of the central issues in synthetic chemistry community for long time.

Biology-oriented arylamine

Materials-oriented arylamine OMe

MeO

O NH HN

MeO

O

OH

HN

NH

HO 2C

H

N

O

N

N

OMe

hole-transporting material for perovskite-sensitized solar cells

O

N

NH

N F

O

N H

O

N

O

O

O

N O

N O

N Imatinib as kinase inhibitor

AcNH antibiotic drug for drug-resistant bacteria

Charge-transporting materials

N

OH

Si

Ar'

R

CO2H

N

OMe

MeO

FR900482 for anti-tumor antibiotic

Martinellic acid

N

NH

O

N H

N Me

OMe

NH HN

N

MeO

OH

N

N

N

+ N

fluorophore for live-cell super-resolution imaging

PCy 2 NMe 2

Me 2N

N

PCy 2 NMe 2

N

N R

Phosphine Ligand for cross couplings

Ar

Zn N

Ar' aminoporphyrin for porphyrin-sensitized solar cells

Figure 1. Examples of functional molecules having arylamine moieties.


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Ullman reported the first example of amination of aryl halides in 1903 (Scheme 1, eq 1).5 In 1983, the pioneering work on palladium-catalyzed amination of aryl bromides was reported by Migita and Kosugi, in which tributyl(N,N-diethylamino)tin was used as an amine source in the palladium-catalyzed C–N bond formation.6 Although their discovery was innovative, the reaction had several drawbacks to be improved: preparation of aminostannane reagents was necessary and toxic triorganotin was inevitably generated as the waste. In 1994, Buchwald7 and Hartwig8 reported palladium-catalyzed amination of aryl halides with simple amines that allows straightforward access to various arylamines. Since then, many chemists have actively studied on transition-metal-catalyzed amination of aryl halides to improve catalysts, expand the scope, and elucidate reaction mechanism (Scheme 1, eq 2).9,10 Although the transformation is efficient and reliable, there are still some drawbacks. Those include the need of preparation of aryl halides (and pseudohalides) or metal reagents prior to the amination (making overall transformation multistep in nature) and the generation of stoichiometric amounts of metal halide wastes after the amination. Thus, if one can directly aminate C–H bonds of aromatic compounds (without using aryl halides as aryl source), many of the drawbacks of state-of-the-art, halide-based amination can be solved. Such direct C–H amination is of great importance to supply various amino compounds with high step efficiency and waste-free strategy. Classically, direct installation of amine moiety into arenes can be conducted by electrophilic aromatic nitration pathway (Scheme 1, eq 3).11 The classical pathway requires several steps: nitration of arenes under strongly acidic conditions, followed by reductive hydrogenation. The harsh reaction conditions limit the substrate scope and render this methodology somewhat less practical. Toward achieving ideal C– N bond forming process, C–H amination of arenes has been intensively studied in the past decade (Scheme 1, eq 4).12


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Ullmann cross-coupling (1903) X +

H 2N

H N

Cu

(1)

harsh conditions X = halogen Buchwald–Hartwig amination Pd or Cu catalyst R1

X +

R1 N

base

H N

(2)

R2

R2 X = (psuedo)halogen Classical nitration pathway H

[NO 2+]

NO 2

NH 2

reduction

R1 N

R2

(3)

Direct C–H amination R1

H +

X N

catalyst

R1 N

R2

(4)

R2 X = halogen, H

Scheme 1. Representative synthetic routes for arylamines.

Overview of this review. This review covers advances in catalytic aromatic C–H amination. Overview of the combinations of substrates and nitrogen sources in the C–H amination is presented in Table 1. An array of recently developed new reactions is categorized as the nature of aromatic substrates and nitrogen sources. The substrate arenes are listed in the order of reactivity: 5-membered heteroarenes S1, arenes having a nitrogen moiety in the molecule S2 (intramolecular C–H amination), arenes having a directing group S3, simple arenes with excess amounts S4, and simple arenes as the limiting reagents S5. The nitrogen sources are listed in the order of versatility: nitrene precursors N1, amines having a leaving group on nitrogen N2, and


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non-activated amines N3. It can be clearly seen from the table that the development of ideal yet hard-to-achieve amination reactions (combinations of S5/N2 and S5/N3) is still in its infancy.

Table 1. Combination of substrates and nitrogen sources.

Arenes

n

Y H

N H

H

DG H

Z

Nitrogen Sources

R Excess or Solvent

n = 1 or 2

S1

S2

H

S3

R

1 equiv

S4

S5 X

N

N1 X

Che, König

Pérez, He

N

N2

H

Nicholas, Sanford, Lee

Baran, Ritter, Itami

Hartwig, Chang, DeBoef, Antonchick

Nicewicz

N

N3

>20 exmamples

6~19 examples

1~5 examples

X No examples

Brief summary of aromatic substrates of C–H amination. The reactions of reactive 5membered heteroarenes (Scheme 2, eq 1) have been well studied and a variety of reactions are reported. Many examples of intramolecular reactions (Scheme 2, eq 2) and intermolecular reactions of aromatics having a catalyst-directing (coordinating) group13 (Scheme 2, eq 3) can be found in the literature with various nitrogen sources. However, the substrate scope of these


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methods is still limited. Recent research interest of C–H amination is focused on the transformation of simple arenes. Due to the low reactivity, simple arenes need to be employed in an excess amount (often used as a solvent) in most cases (Scheme 2, eq 4). Recently, several methods allowing using simple arenes as limiting reagents have been reported (Scheme 2, eq 5). (1) Heteroaromatic C–H amination Y

Y

catalyst H

+

N

N

Z (2) Intramolecular C–H amination

n

N H

(1)

Z

catalyst

n

N (2) n = 1 or 2

(3) ortho-Directing C–H amination DG H

DG

catalyst +

N

N

(3)

(4) Intermolecular C–H amination of arenes with excess amounts H

N

catalyst +

N

(4)

R excess or solvent

R

(5) Intermolecular C–H amination of arenes as the limiting reagent H R 1 equiv

N

catalyst +

N

(5) R

Scheme 2. Variation of aromatic substrates for C–H amination.


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Brief summary of nitrogen sources of C–H amination. The variation of nitrogen sources of C–H amination is summarized in Scheme 3. Nitrenes and metal nitrenoids, which can be generated from organic azide14 or [N-(arylsulfonyl)imino]phenyliodinane15, can be inserted into C–H bonds of organic compounds, resulting in the formation of corresponding amines. While nitrenes and metal nitrenoids have been intensively exploited for sp3 C–H amination,16,17 application to aromatic substrates lags behind because the control of regioselectivity is particularly difficult (Scheme 3, eq 1). The use of catalyst-directing groups on substrates is advantageous to control the regioselectivity via the formation of a metallacycle. Other nitrogen sources have been also developed. An interesting solution is umpolung of nitrogen atom in the coupling reaction from nucleophile to electrophile. A variety of nitrogen electrophiles, such as N-halides, N-carboxylate, and N-tosylate, have been applied to aromatic C–H amination (Scheme 3, eq 2). From the viewpoints of step-economy and versatility, aromatic C–H amination with simple and non-activated amine, amide, and imide, which are the most diverse nitrogen sources, is an ideal transformation (Scheme 3, eq 3).


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(1) Amination with nitrene precursor H N + R1 nitrene

H N

R1

(1)

nitrene precusor: TsN3, Ar-N3, PhI=NR (2) Amination with amines having a leaving group on nitrogen R2 R2 H N + R3 N 3 X R

(2)

X= halogen, OTs, OBz (3) Amination with non-activated amines R2

R2

H

+

[O]

N

H

N

R3

(3)

R3 [O] = external oxidant

Scheme 3. Variation of nitrogen sources for C–H amination.

1. C–H amination of 5-membered heteroarenes High prevalence of amine-functionalized heterocyclic compounds in biologically active natural products and pharmaceuticals has stimulated scientists to search for a straightforward C– H amination protocol. Among heteroaromatic compounds, 5-membered heteroarenes are known to be reactive, and many C–H amination reactions have therefore been reported. 1-1. Amination with nitrene precursors Transition-metal-catalyzed nitrene insertion into C–H bonds is an attractive strategy for C–N bond formation. In 2004, Che described a pioneering example that a ruthenium porphyrin can catalyze nitrene insertion to heteroaromatic C–H bond with N-(p-toluenesulfonyl)-


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iminophenyliodinane (PhI=NTs) or PhI(OAc)2/NH2SO2R as a nitrogen source.18 As shown in Table 2, furan, thiophene, and N-tosylpyrrole undergo the C–H insertion to provide the corresponding imidation products. The “expected” amidation products were not formed under these conditions, while the reason is not clear. In contrast, the reactions of N-alkyl or arylpyrroles and indole provided the doubly amidated products.


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Table 2. Ruthenium-catalyzed imidation of furans, thiophenes, and pyrroles. Me

CO

RuII(TTP)(CO) (10 mol%) + Z

PhI

Z = O, S, NAr 1 equiv

NR1

Z

CH2Cl2, ultrasound 40 °C, 2 h

NR1R 2

N Me

R1

= Ns, Ts R 2 = H or R1

5 equiv

N Ru N N

Me

RuII(TTP)(CO) Selected Substrate Scope

Me

[Imidated products] NTs 2

O

NNs 2

O

73%

63%

NTs 2

S

33%

N Ts 33%

NTs 2

PhN

N NTs 91%

[Amidated products] TsHN

NHTs

TsHN

NHTs

TsHN

NHTs

TsHN

NHTs

3

NHTs N Me

68%

N

N

N

N

2

Me

82%

60%

NO 2 87%

64% C2:C3 ratio not determined

Che reported a rare example of 2,3-diimination of indoles with aryl azides in the presence of Ru(TTP)(CO) catalyst (Scheme 4).19 An active ruthenium–nitrene species is thought to be formed from ruthenium catalyst and aryl azide, which undergoes aziridination of indoles followed by ring-opening, nitrene C–H insertion, and hydrogen abstraction to provide 2,3diimination products.


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N R 1 equiv +

R'

H NAr

cat. [Ru(TTP)(CO)]

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ring-opening nitrene C–H insertion

N H R

ClCH2CH2Cl reflux

N3 NHAr

3.1 equiv R' = 4-NO2 or 3,5-(CF3)2

R'

N

R'

NHAr N R

N N R

20 examples 50-94%

Scheme 4. Diimination of indoles with aryl azides.

Very recently, König reported a new C–H insertion approach using photoredox catalysts. Under the influence of Ru(bpy)3-based photoredox catalyst, C–H amidation of 5-membered heterocycles (furan, pyrrole, and thiophene) can be achieved with benzoyl azide under blue LED light irradiation (Scheme 5).20 The proposed mechanism is shown in Scheme 6. Ruthenium catalyst is excited to a triplet state with blue light irradiation, which acts as sensitizer for benzoyl azides. The activated benzoyl azides lose dinitrogen to yield the benzoyl nitrene. As the addition of an acid is essential for the amidation reaction, the authors postulated that the benzoyl nitrene might be protonated by the acid. The protonated nitrene reacts with arenes to afford the corresponding amidated products.


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Ru(bpy) 3Cl2⋅6H 2O (2.5 mol%)

H

+

Z

5 equiv Z = N, NMe, O, S

N3

H N

H 3PO 4 (2 equiv)

Ar

Ar

O

DMSO rt, 2-25 h

Z

1 equiv

455 nm blue LED

> 25 examples 15-88%

O

Scheme 5. Photocatalytic C–H amidation with benzoyl azides. Blue light

Ru(bpy) 32+* Ru(bpy) 32+ N3

* –N2

N3 O

N O

O H+

–H+

H H N Z

Ar

H N

+

–H+

Z

O

Ar

Z

H N+

O

O

Scheme 6. Proposed mechanism.

1-2. Amination with amines having a leaving group on nitrogen Amines having a leaving group on nitrogen, such as N-haloamines or N-oxyamine, can be employed in C–H amination as a nitrogen cation equivalent. One of the earliest protocols is copper-catalyzed amination of azoles with N-chloroamine, which was disclosed by Miura (Table 3).21 The reaction is thought to undergo through (1) base-assisted cupration of azole, (2) oxidative addition of N-chloroamine to the resulting heteroaryl Cu(I) intermediate to form a Cu(III) complex, and (3) reductive elimination from the Cu(III) complex to provide the product (Scheme 7). These conditions were also applicable for the reactions of substrates having acidic


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C–H bonds, such as pentafluoroarenes, azoles, and quinoline N-oxides, with N-carboxyamines as a nitrogen source.22

Table 3. Copper-catalyzed amination of azoles with chloroamines at room temperature. Cu(acac)2 (10 mol%) bpy (10 mol%) Z N

H

+

R1

O

Cl

N R2

1 equiv

1.5 equiv

LiOtBu or NaOtBu (2 equiv)

Z N

toluene, rt, 2 h

O

R1 N R2

Substrate scope (Selected) N N

N N

O

N

O

R

R R R R R

Ph

Ph

R

N N

O

O

R R R R

N

68%

N

N

N N O

63%

O

69%

O

O

= H: 81% = 4-MeC6H 4: 70% = 4-MeOC6H 4: 72% = 4-CF3C6H 4: 62% = 4-ClC6H 4: 84%

N N

N

= H: 76% = Ph: 62% = Me: 53% = Cl: 73%

N O

66%


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N

R1

O

N R2

N

Cu(II)

H O

Cu(I) (3) reductive elimination

N

(1) base-assisted cupration

R1 N R2

(2) oxidative addition

Cu(III) O

Cl Cl

N Cu(I) O

R1 N R2

Scheme 7. Proposed mechanism. Liu reported an interesting amination co-catalyzed by palladium and copper (Scheme 8.).23 Regioselective amidation and chloroamidation of indoles using N-chloro-N-alkylarylsulfonamides at room temperature were disclosed. At the initial stage, Liu found that the addition of bpy was essential for the amidation when 1.8 equiv of N-chlorosulfonamide was employed. In the absence of bpy, employment of 3 equiv of N-chlorosulfonamide drastically changed the product to the corresponding chloroamidated indole. The mechanism is unclear at this stage. In 2014, Hocek expanded the substrate scope to pyrrolo[2,3-d]pyrimidine (7deazapurines).24 Related to these works, Nicholas reported copper-mediated difunctionalization reaction of indoles with benzophenone O-acetyloxime that installs diphenylimino group and bromo group at the C2- and C3-positions of indole ring, respectively.25


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H Pd(OAc) 2 (5 mol%)

H

Cu(acac)2 (10 mol%)

N R1

bpy (10 mol%)

H R2

Na 2CO 3 (2 equiv)

N N R1

+

dioxane, rt, 14 h

Ts

Cl

R2 N Ts

Pd(OAc) 2 (2.5 mol%) CuCl (10 mol%) Ag2CO 3 (2 equiv)

Cl

LiCl (2 equiv) dioxane, rt, 14 h

N R1

R2 N Ts

[Comparison of the reactions] Pd(OAc) 2 (5 mol%)

• Amidation

Cu(acac)2 (10 mol%) Ag2CO 3 (2 equiv)

H H + Cl N Me

Me N Ts

H

bpy (10 mol%) dioxane, rt, 14 h

(1.8 equiv)

Cl Me + N Ts

N Me 50% (92% after optimization)

N Me 0%

H

Cl

Me (1) N Ts

• Chloroamidation Pd(OAc) 2 (5 mol%) Cu(acac)2 (10 mol%)

H H + Cl N Me

Me N Ts

Ag2CO 3 (2 equiv) dioxane, rt, 14 h

(3 equiv)

(no reaction when 1.8 equiv)

N Me

Me + N Ts

0%

N Me

Me (2) N Ts

37% (85% after optimization)

Scheme 8. Pd/Cu-catalyzed amidation and chloroamidation of indoles.

Recently, formal copper-catalyzed aromatic C–H amination reaction with Nacyloxyamines was reported (Scheme 9).26 The amination most likely proceed with in situ formed arylzinc reagents that can be generated by the abstraction of an acidic proton on the aryl ring with the zinc base Zn(tmp)2 (tmp = 2,2,6,6-tetramethylpiperidide). The resulting arylzinc reagents reacted with N-benzoyloxyamine to afford the corresponding aminated products. This


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protocol not only allows highly efficient reaction under mild conditions, but also manifests good substrate compatibility with both electron rich and deficient heteroarenes.26a

+

Ar H

2.1 equiv

N

Zn(tmp)2

Ar =

1 equiv

ZnX

+

N

N

Z = O, S, NMe

THF, 1 h Ar

Fn

R Z

Z

BzO NR1R 2

1 equiv

Cu(OAc)2 (10 mol%)

Ar NR1R 2 40 examples 60-98%

THF, rt, 5 h

Scheme 9. Copper-catalyzed electrophilic amination with in situ-generated arylzinc reagent.

In recent years, N-fluorobenzenesulfonimide (NFSI) has received increasing attention and several reports on imidation with NFSI have been disclosed.27 For example, imidation of thiophenes, furans, and pyrroles with NFSI can be promoted in the presence of a catalytic amount of CuI (Scheme 10).28

R

+

Z Z = S, O, NR

1 equiv

PhO 2S

SO2Ph N F (NFSI)

1.2 equiv

CuI (5 mol%) ClCH2CH2Cl 60 °C, 8 h

R Z

N(SO 2Ph) 2

23 examples 78-93%

Scheme 10. Copper-catalyzed imidation of thiophenes, furans, and pyrroles.

N-Haloamine and N-oxyamine have proved to be a good precursor for nitrogen-centered radical for C–H amination of heteroarenes. The details about radical process will be explained


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later in the section of amination of simple arenes. Inspired by MacMillan’s work,29 photoredox catalyzed C–H amination of 5-membered heterocycles with N-sulfonyloxyamine derivatives was recently reported, giving the corresponding amidated indoles, pyrroles, and furans (Scheme 11).30 Similarly, photoredox catalyzed amination of oxazoles with N-chloroamines was reported in 2014.31 fac-Ir(ppy)3 (2 mol%) H

R PhO 2SO N SO2Ph

+

Z 1 equiv Z = NR, O

NaHCO 3 (1.2 equiv) DMF, rt

2 equiv

[Proposed Mechanism] R PhO 2SO N SO2Ph

Z

white LED

R N SO2Ph


IrIII*

N

R N SO2Ph

Ir N IrIV

N

IrIII

H fac-Ir(ppy)3

Z

Z

R N SO2Ph H

+ Z

R N SO2Ph H

–H+

Z

R N SO2Ph

Scheme 11. Photoredox catalyzed C–H amination of indoles, pyrroles, and furans.

Chang32 and Yu33 reported the amination of benzoxazoles with formamides as surrogates of amines through a slow decarboxylation process (Scheme 12, eq. 1). They revealed that simple amines were more reactive so that the reaction can proceed without the use of excess amount of


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amines (Scheme 12, eq. 2). The mechanism is proposed that (a) azoles are activated with proton or metals, (b) amines nucleophilically attack the activated azoles, and (c) the resulting intermediates are rearomatized through oxidation with Ag or Fe. TBAI-catalyzed (transitionmetal-free) amination of benzoxazoles with formamides was reported by Wang.34


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O

Z H

R

+

H

N R2

N

Ag2CO 3 mediated (Chang) or FeCl 3 catalyzed (Yu)

Z R N

R1 N R2

(1)

R1 N R2

(2)

>25 equiv

1 equiv

Z H

R

R1

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H

+

N

1.2–1.5 equiv

N R2

Ag2CO 3 mediated (Chang) or FeCl 3 catalyzed (Yu)

R1

Z R N

1 equiv

[Proposed Mechanism]

Z N

(a) activation with H+ or Lewis acid (LA)

Z N+ H/LA

(c) oxidation R1 with Ag or Fe N N + R2 H/LA

(b) nucleophilic attack H

N R2

Z

R1

Z N

R1 N R2

O

gradually decomposed with heat or acid

H

N R2

R1

Scheme 12. Amination of azoles with formamides and simple amines as nitrogen sources.

Palladium/copper-catalyzed C–H amination of benzoxazole with sulfamoyl chlorides was developed by Chen.35 The copper catalyst might assist the formation of an oxazolylpalladium(II), which may react with sulfamoyl chloride to give a Pd(IV) intermediate. The Pd(IV) releases SO2 to form an oxazolylaminopalladium(IV) intermediate, from which the corresponding product is generated through reductive elimination (Scheme 13).


20

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ACS Catalysis

PdCl 2(bpy) (10 mol%) CuCN (20 mol%) O H

R N

1 equiv

+

O O R1 S Cl N R2 1.5 equiv

K 2CO 3 (2 equiv) K 2Cr2O7 (1 equiv) PhCl, 150 °C, 24 h under air

O R N

R1

O

O Cu

N

O Pd(II)

N

R2 N O S O

R1 N R2

R1

O

Pd(IV)

N

R2

Pd(IV)

N

N

Cl

Cl SO2

Scheme 13. Pd/Cu-catalyzed amination of benzoxazoles with sulfamoyl chlorides.

1-3. Amination with non-activated amine Aromatic C–H amination through direct transformation of an N–H bond of a simple amine is most ideal because pre-functionalization of nitrogen is unnecessary. While most reactions require organic/inorganic oxidants, recent development has enabled to use molecular oxygen as the most abundant and environmental friendly oxidant for such oxidative processes. The early examples using non-activated amine as nitrogen source for amidation and amination of azoles at the C2-position under aerobic conditions were reported by Schreiber36 (Scheme 14, eq. 1) and Mori37a (Scheme 14, eq. 2). The reaction is likely initiated by deprotonation of the most acidic proton of C2, which was already mentioned in Scheme 7. Schreiber applied this reaction to amidation of multifluoroarenes. Mori then expanded the scope to cover thiophenes.37b Similarly, Su reported copper-catalyzed amination of acidic aryl C–H bonds of perfluoroarenes and azoles.38 The reaction successfully used primary aniline derivatives as nitrogen sources. Copper(I) bromide catalyzed C–H/N–H dehydrogenative sulfoximination of quinoline N-oxides


21

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Page 22 of 86

(Scheme 14, eq. 3)39a,b, quinoline,39c, or azoles and perfluoroarenes39d under aerobic conditions. Hirano and Miura showed that the reaction of azoles with 2-alkynylanilie afforded Nazolylindoles (Scheme 14, eq. 4).40 The reaction proceeded through an oxidative C–H/N–H coupling/annulation sequence. Copper(II) chloride complexes of 1° and 2° amines were proved to be good nitrogen sources for amination of benzoxazoles, benzothiazoles, and Nmethylbenzimidazoles, albeit stoichiometric in copper.41 Notably, Huang reported coppercatalyzed oxidative amination of benzoxazoles with tertiary amines such as triethylamine as nitrogen sources (Scheme 15).42


22

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ACS Catalysis

•Schreiber

Cu(OAc)2 (20 mol%) Z H

R

+

N

1 equiv Z = S, O, NMe

Na 2CO 3 (2 equiv)

O Y R1 H N R2

pyridine (20 equiv) toluene, 120–140 °C 12–30 h

5 equiv Y = C or SO

•Mori

X R N

O X R1 N R2

(1)

O2 (1 atm)

Cu(OAc)2 (20 mol%) Z H

R

+

N

1 equiv X = S, O, NMe

R1 H N R2

xylene, 140 °C, 20 h

4 equiv

O2 (1 atm)

PPh 3 (40 mol%)

Z R N

R1 N R2

(2)

•Bolm

N+ O–

H

+

O R1 H S N R2

toluene, 50 °C 48 h, air

(3)

4 equiv

1 equiv

Cu(OAc)2 (20 mol%)

•Hirano and Miura R' Z H

R

O R1 S N+ N R2 O–

CuBr (5 mol%)

+

H H N

R'

phen (20 mol%) Z

K 2CO 3 (1 equiv)

N

toluene, reflux 10 h

N

N

R

(4)

O2 (1 atm) Z R

oxidative C–H/N–H coupling

N

H N

R'

annulation

Scheme 14. Copper-catalyzed oxidative amination of azoles and quinoline N-oxides with amines under aerobic conditions.


23

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 24 of 86

CuBr2 (10 mol%) O H

+

N

1 equiv

AcOH (20 mol%)

O

1,4-dioxane, 120 ˚C

N

N

2 equiv

N

O2 (1 atm)

Scheme 15. Copper-catalyzed amination of oxazoles with tertiary amines.

Hydrogen peroxide and alkyl hydroperoxides can be used as practical oxidant for amination of heteroarenes. Chang reported cobalt- and manganese-catalyzed amination of benzoxazoles, benzothiazoles, and an oxadiazole in the presence of tBuOOH (Table 4).43 Co(OAc)2 proved to be suitable catalyst for amination with dialkylamines and no product was obtained when monoalkylamines or ammonia was used as a nitrogen source. On the other hand, Mn(OAc)2 showed catalytic activity in the reaction with monoalkylamines and ammonia. Manganese also catalyzes amination of an oxadiazole with a dialkylamine.


24

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ACS Catalysis

Table 4. Cobalt- and manganese-catalyzed amination of azoles by using peroxides as an oxidant. cat. Co(OAc)2 or Mn(OAc) 2 tBuOOH (1.2 equiv) R1

N H

+

H N R2

O

AcOH (1.2 equiv)

N

MeCN, 25 °C, 12 h

O

R1 N R2

[Selected substrate scope] cat. Co(OAc)2: 2° amine Me

cat. Mn(OAc) 2: 1° amine or NH 3 Me

N

N

N O

O

81%

75% Me

N N

N

O

S

O

40%

66%

Cl

N

H N

Me

N

O

O

0% Me

H N

H N H

25% N O

0%

H N

H N H

N N Ph

Me N

O

41%

Sun and Zhao reported copper-catalyzed C–H/N–H-type imidation of furans, thiophenes, and pyrroles by using tBuOOH as an oxidant (Scheme 16.).44 Li and Duan showed the same reaction with nickel catalyst.45 Heterogeneous γ-MnO2-catalyzed oxidative amination of benzoxazoles was reported.46 The proposed mechanism is similar with Scheme 12. An oxazole reacts with an amine to give 2-aminobenzoxazolidine, which is oxidized by oxygen with the aid of γ-MnO2.


25

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

O H

+

Z

1 equiv Z = S, O, NH, NMe

R1

Page 26 of 86

Cu(OAc)2 (10 mol%)

O

tBuOOH (2 equiv)

H N S O O

R1

N R2

MeNO 2, 120 °C

Z

S O O

R2

2 equiv

Scheme 16. Copper-catalyzed imidation by using tert-butyl-hydroperoxide as an oxidant.

Although the reaction mechanisms are unclear, combinations of peroxides and catalytic amount of iodine source such as TBAI,47a,b NIS,47c or I247d–f were efficient for amination of oxazoles47a-d or indoles47e,f. In the case of benzoxazole substrates, formal C–H amination with amine is possible.48 For example, in the presence of oxidant such as PhI(OAc)2,48a TEMPO+BF4–,48b FeCl2/H2O2,48c IBX,48d and NBS48e, amination reaction of benzoxazoles with amine can proceed (Scheme 17, eq. 1). The reaction is thought to take place through amine addition and ring opening of oxazole ring giving o-hydroxyamidine, followed by oxidative ring closure. Additionally, the mixture of benzoxazole and amine in the presence of base and I2 afforded 2-aminobenzoxazoles via 2-iodobenzoxazoles as an intermediate (Scheme 17, eq. 2).49 Similarly, iodine-mediated reactions of indoles with morpholine50a and sulfonylamide50b were reported (Scheme 17, eq. 3). Formal C–H amination of heteroaromatics via λ3‑iodane intermediates were reported.51


26

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ACS Catalysis

N H O

R1 N OH R2 o-hydroxyamidine

R1 H N R2

+

N

[O]

N

O

R1 N R2

(1)

[O] = PhI(OAc) 2, TEMPOBF4, FeCl 2/H2O2, IBX, NBS N H O

R1 H N R2

+

N

I2

SN Ar

I O

N

O

R1 N R2

(2)

2-iodobenzoxazole I H N Me

I+

I2 Ar H N

Ar

Ar N

N

N Me

N Me

SO2Ar'

N Me

(3) SO2Ar'

SO2Ar'

Scheme 17. Metal-free formal amination of benzoxazoles and indoles.

2. Intramolecular C–H amination52 2-1. Amination with nitrene precursors Early studies on non-catalytic intramolecular C–H amination of aryl or alkenyl azides required high temperatures (Scheme 18, eq. 1)53a or stoichiometric amount of promoters such as AlCl3 (Scheme 18, eq. 2)53b. In 2007, Driver54 reported new catalytic indole synthesis through rhodium-catalyzed intramolecular C–H amination using azide via a nitrene insertion of C–H bond (Scheme 19).54a They further expanded the substrate scope of rhodium–nitrene-catalyzed aromatic C–H amination to o-vinylarylazide54b and o-arylazide54c,d. Similarly, intramolecular C– H amination reactions of aryl azide were reported in the presence of ruthenium55a,b or copper55c as a catalyst.


27

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 28 of 86

[Rees] H R O H

R

CO2Me

+ N3

R

CO2Me H

N3

toluene reflux

N H

CO2Me

(1)

[Takeuchi] AlCl3 (1.05 equiv)

(2) N H

CH2Cl2, rt

N3

89%

Scheme 18. Stoichiometric intramolecular C–H amination using aryl or alkenyl azides.

R

CO2Me H

cat. Rh 2(O 2CC 3F 7)4

N3

toluene, 30-60 °C

R

CO2Me H

N

[Rh]

R N H

CO2Me

Scheme 19. Rhodium-catalyzed intramolecular C–H amination using azide.

Chiba utilized α-aryloxime as a metal-nitrene precursor, from which intramolecular C–H amination proceeded to construct indole frameworks under palladium catalysis (Scheme 20).56 The detailed mechanistic study was conducted using deuterium-labeled oxime as a substrate. For example, the observed kH/kD ratio of 1:1 using this substrate (intramolecular competition experiment) indicated that the reaction presumably underwent through an electrophilic aromatic substitution mechanism.


28

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ACS Catalysis

O O

PdCl 2(MeCN) 2 (25 mol%)

N Me N

O

O

N

MgO (5 equiv)

Me

CH2Cl2, 80 °C, 3 h

N H 82%

OCO2C6F 5

[KIE experiment]

D

Me N Me Me

O

H

N

PdCl 2(MeCN) 2 (25 mol%)

D

MgO (5 equiv)

O

CH2Cl2, 80 °C, 3 h

OCO2C6F 5

Me N Me

O

H +

Me

Me

N H

49%

Me N Me

N H

kH /kD = 1:1

[Proposed mechanism] R1

H

R2 N

OCO2C6F 5 R1 R2 N Pd

R1

R1 R2 N

Pd

R2 N

OCO2C6F 5

electrophilic aromatic substitution

Pd

OCO2C6F 5

–

+

R1

R1 R2

N H Pd –

R2 N H

Scheme 20. Palladium-catalyzed reaction of α-aryloxime.

2H-Azirines, isolable equivalents of nitrenes, have been applied to indole synthesis through intramolecular C–H amination. In 1968, Taniguchi showed that thermal decomposition of 2H-azirine provided indole in good yield (Scheme 21, eq. 1).57a Taber took advantage of Neber route58 from

α-arylketones for preparation of 2H-azirines, which underwent thermal

transformation into indoles (Scheme 21, eq. 2).57b Palladium-59a, rhodium-59b, and iron-59c catalyzed synthesis of substituted indoles were then reported (Scheme 22). The reactions proceeded at 30–80 °C to provide a variety of 2,3-disubstituted indoles in good yields.


29

ACS Catalysis

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Page 30 of 86

[Taniguchi] Me N3

ligroin (bp. 100-105 °C) reflux

[Taber]

N

C16H 34 (bp. 287 °C) 2-phenyl-3-methyl-2H-azirine reflux quant.

(1) H 2N-OH Me (2) MsCl, Et 3N, DBU O

Br

Me

Me

N Br

Me

Me o-xylene Br 170 °C, 18 h

78%

N H >86%

(1)

(2)

N H 88%

Scheme 21. Thermal decomposition of storable 2H-azirine into indoles.

Pd: Taniguchi Rh: Narasaka Fe: Zheng

R1 N

R1

R2

R2 N H

Scheme 22. Metal-catalyzed reactions of 2H-azirines.

Nitroarenes60 and nitroalkenes61 have proven to be a good precursor of nitrenes in the presence of metal catalyst under reductive CO60a,b, 61 or H260c atmosphere. In 2009, Dong reported palladium-catalyzed synthesis of indoles under CO atmosphere (Scheme 23).61a They proposed the reaction mechanism consisting of (1) cyclization of nitroalkene with palladium(0) and CO forming a palladacycle, (2) extrusion of CO2 from the palladacycle to give an η2-bound nitrosoalkene complex, (3) electrocyclization and H-shift to generate N-hydroxyindole, and (4) palladium- and CO-mediated reduction to yield NH-free indole (final product).


30

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ACS Catalysis

Pd(OAc) 2 (2 mol%)

R

R

1,10-phen (4 mol%) CO (1 atm)

NO 2

N H

DMF, 110 °C [Proposed mechanism] R

R

R

Pd NO 2 CO

O R

electrocyclization

N

O Pd

N

–CO2

Pd

O

N+ O–

R

H-shift

Pd

Pd

N O H

O

CO –CO2

R

N H

Scheme 23. Palladium-catalyzed synthesis of indoles from nitroalkenes.

2-2. Amination with amines having a leaving group on nitrogen Hartwig envisioned that readily available O-acyloximes would be suitable substrates for intramolecular aromatic C–H amination providing indoles (Scheme 24).62 The key Pd(II) intermediate (N–O bond oxidative addition complex) was synthesized from O-acyloximes and Pd(PCy3)2 and characterized by X-ray crystallography. Treatment of the Pd(II) complex with cesium carbonate in toluene at 150 °C afforded the indole product. These results suggest that the reaction proceeds through oxidative addition of N–O bond to Pd(0), followed by intramolecular C–H palladation and reductive elimination.


31

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

N

R1

OAc R2

Pd(dba) 2 (1 mol%) Cs2CO 3 (1 equiv)

Page 32 of 86

H N R1

R2

toluene, 150 °C, 24 h

R3

R3

14 examples 40-71%

R1 = alkyl, alkoxy, halogen R 2 = Me, Et; R 3 = Ar [Mechanistic study] N

OCOC6F 5 Me

Pd(PCy 3)2 (1 equiv) toluene, rt

C6F 5OCO PCy 3 Pd Cy 3P N Ph Me

56% isolated yield

Cs2CO 3 (1 equiv)

H N Me

toluene,150 °C, 2 h 31%

X-ray

Scheme 24. Palladium-catalyzed intramolecular C–H amination of O-acyloximes.

The ring-closing, intramolecular amination reactions of O-acyloximes have been widely applied to the synthesis of 6-membered nitrogen heterocycles.63,64 Yoshikai disclosed ironcatalyzed cyclization reaction of O-acetyloxime that provided phenanthridines (Scheme 25, eq. 1).63a They proposed that iron activates O-acetyloxime via coordination to facilitate cyclization reaction. Zhang utilized Yoshikai’s conditions to synthesize pyrrolo[1,2‑a]quinoxaline derivatives (Scheme 25, eq. 2).63b Roy developed Pd/Cu-based bimetallic catalytic system for the synthesis of indoloisoquinolines through intramolecular C–H amination of O-methyloxime (Scheme 25, eq. 3).63c Chiba used copper as a catalyst for C–H amination through a radical process (Scheme 25, eq. 4).63d Relatedly, an intramolecular C–N bond-forming reaction via N–Cl bond cleavage under photo-irradiated conditions was reported.63e


32

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ACS Catalysis

[Yoshikai] OAc

R

Fe(acac) 3 (20 mol%)

N

O

via

R N

Fe(III) R

AcOH, 80 °C, 24 h

O N

(1)

[Z. Zhang, G. Zhang] OAc

R

R Fe(acac) 3 (20 mol%)

N

N (2)

AcOH, 80 °C, 2–12 h

N

N

[Roy] OMe N N

R

Pd(OAc) 2 (10 mol%)

N

Cu(OTf)2 (20 mol%)

N

OPiv N

R'

N O

(3)

o-xylene, 110 °C, 2–4 h

[Chiba] R

R

via

CuI (10 mol%)

R

m-xylene, 130 °C under Ar, 16–45 h

R N

K 3PO 4 (1 equiv) R'

N O

N R'

N

(4)

O

Scheme 25. Synthesis of 6-membered heteroaromatics through intramolecular C–H amination. Shi reported an interesting reaction of α-methylstyrenes with diaziridinone catalyzed by palladium that gave a series of spirocyclic indolines (Scheme 26, eq. 1).65 Shi then utilized diaziridinone as a tert-butylamine sources to access indolines (Scheme 26, eq. 2).66


33

ACS Catalysis

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Pd(PPh 3)4 (10 mol%)

O +

Page 34 of 86

N

N

O

N

PPh 3 (20 mol%)

N

(1)

N

(2)

neat, Ar, 85 °C, 24 h N

1 equiv

4 equiv 75% Pd(PPh 3)4 (10 mol%) norbornene (2 equiv)

O

I +

N

N

R 1 equiv

Cs2CO 3 (2 equiv) toluene, 80 °C, 48-72 h

R

1.5 equiv

Scheme 26. Palladium-catalyzed reaction of α-methylstyrenes with diaziridinone.

2-3. Amination with non-activated amine Oxidative cross-dehydrogenative coupling (CDC) between C–H bond of an aromatic compound and N–H bond of an amine (C–H/N–H coupling) represents one of the most ideal ways to accomplish C–H amination. The first example was reported by Buchwald in 2005.67 Palladium acetate was employed as a catalyst for this reaction and O2 and Cu(OAc)2 were used as oxidants (Scheme 27). This protocol provides an efficient synthetic route to N-acylcarbazoles through intramolecular CDC amination. Gaunt reported another example using PhI(OAc)2 as the oxidant to accomplish a room temperature C–H amination (Scheme 28.).68 Palladium-catalyzed intramolecular C–H amination was widely applicable to the synthesis of nitrogen-containing heteroaromatics (Table 5.) such as N-alkyl-68 or N-arylcarbazoles69, N-sulfonylcarbazoles,67b,70 Narylindazo[3,2-b]quinazolinones,71 phenanthridines,72 phenanthridinones,73 indoles,74 indolines,75 benzotriazoles,76 imidazoles,77 lactams,78 quinolinones,78,79 and indazoles80.


34

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ACS Catalysis

In addition to palladium-based catalytic systems67-80, copper catalysts have been also extensively investigated for intramolecular CDC amination.81 As an inexpensive and practical alternatives of noble transition metals for these reactions, iron-catalyzed82 or organocatalytic83 protocols were proven to be efficient.

O

R1

R2

N H H

Pd(OAc) 2 (5 mol%) Me

R1 O

Cu(OAc)2 (1 equiv)

N Me

toluene, 120 °C 12-24 h R2

O2 (1 atm)

18 examples 41-98%

R1, R 2 = H, alkyl, alkoxy

Scheme 27. Buchwald’s palladium-catalyzed synthesis of N-acylcarbazole.

R1

R2

N H H

Alkyl

Pd(OAc) 2 (5 mol%)

R1

PhI(OAc) 2 (1.2 equiv)

N Alkyl

toluene, rt R2

Scheme 28. Gaunt’s conditions for intramolecular C–H amination at room temperature.


35

ACS Catalysis

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Page 36 of 86

Table 5. Synthesis of nitrogen-containing heteroaromatics by palladium-catalyzed C–H/N–H coupling

O O N S R

O N

N Alkyl or Ar R

N-acylcarbazoles67

N-alkyl-68 or N-arylcarbazoles69

N-sulfonylcarbazoles67b, 70

N

phenanthridines72 N N

OMe

phenanthridinones73 R

N Ar

benzotriazoles76 R

N

N

indoles74 R1

N R1

imidazoles77

O O N S R

N N

N-arylindazo[3,2b]quinazolinones71

R1

O N

O N

R2 N Ar or Tf

indolines75

O

O N Ar or Tf

lactams78

N

Ts or OAlk

quinolinones78,79

N N R

indazole80

The use of a directing group on nitrogen is a useful strategy in intramolecular C–H/N–H coupling reactions. Chen84a and Daugulis84b independently reported palladium-catalyzed intramolecular C–H/N–H coupling reactions by using picolinamides84a-d as a directing group


36

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ACS Catalysis

(Scheme 29). Owing to the assistance of the directing group, the reaction could be performed under mild reaction conditions that labile functional group such as iodide remained intact. The application of C–H/N–H coupling to the synthesis of glucosylated compounds was also reported (Scheme 30, eq. 2).84b Several researchers developed other directing groups (Table 6) such as 2pyridinesulfonyl group,84e oxalyl amide group,84f and 1,2,3-triazole-4-carboxyl group.84g It has been proposed that these Pd-catalyzed C–H amination processes might involve a Pd(II)/Pd(IV) redox cycle.

HN

R

O

Pd(OAc) 2 PhI(OAc) 2

R

toluene

N

N

O

N

R

Pd

O

N

N

Scheme 29. Picolinamide-assisted intramolecular C–H amidation.

I

I

I Pd(OAc) 2 (2 mol%) HN

O

toluene, Ar, 60 °C, 24 h

N

N

PhI(OAc) 2 (2.5 equiv)

O

N

Pd

(1)

O

N

N

90% BnO

BnO BnO BnO

O

O

OAc BnO

CO2Bn HN N

O

Pd(OAc) 2 (2 mol%)

BnO BnO

PhI(OAc) 2 (2 equiv) toluene, Ar, 60 °C, 3 d 59%

O

O OAc BnO

N N

CO2Bn

(2)

O

Scheme 30. Chen’s application of picolinamide-assisted intramolecular C–H amidation.


37

ACS Catalysis

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Page 38 of 86

Table 6. Other directing groups for intramolecular C–H amination.

CO2Me HN

O S O

HN

O

O

N

N

HN

O

N N N Bn

2-pyridinesulfonyl group84e

oxalylamide group84f

1,2,3-triazole-4-carboxyl group.84g

Hirano and Miura utilized the picolinamide directing group for Cu-catalyzed intramolecular C–H amination to provide carbazoles (Scheme 31)85a and indolines (Scheme 32)85b. This reaction proved to be facile and practical, displaying wide substrate scope. Cu(OAc)2 (30 mol%) R2

R1

O

NH H N

MnO 2 (2 equiv) AcOH (1 equiv) DMF, microwave

R1

200 °C, 1 h

N H 24 examples 55-96%

R2

R1, R 2 = alkyl

Scheme 31. Copper-catalyzed synthesis of carbazoles. Conditions A: Cu(OAc)2 (20 mol%) MnO 2 (6 equiv) or

R2 R1

HN H

N

O

Conditions B: Cu(OAc)2 (2 equiv)

R2 R1 N

DMF, microwave 200 °C

N

O

NaOH

R2 R1 N H

Scheme 32. Copper-catalyzed synthesis of indolines.


38

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Compared to N-substituted amino group, a free amino group has been less frequently utilized as a directing group due to its propensity of tight coordination to transition metals, thereby suppressing catalytic processes. Very recently, Satoh and Miura succeeded in incorporating a free amino group into aminative CDC process by using iridium(III) catalyst.86 This reaction allows accessing a range of carbazoles from simple 2-amino biphenyls in one step (Scheme 33). Same transformation was previously achieved by Matsubara using a Pt/C catalyst under harsh conditions (>250 °C).87 Shown in Scheme 34 is a plausible mechanism that includes amine-directed C−H bond cleavage to form an iridacycle intermediate, followed by C–N bond formation through reductive elimination.

[Cp*IrCl 2]2 (2 mol%) R1

R2

NH 2 H

Cu(OAc)2 (20 mol%) PivOH (2 equiv)

R2

R1

NMP, 120 °C, 3 h air (1 atm)

N H

Scheme 33. Carbazole synthesis from 2-aminobiphenyls.


39

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H 2O

2 CuX

Cp*IrX2 NH 2

air, 2 HX 2 CuX2

H

Cp*Ir H 2N

IrX 2 Cp*

N H

2HX HN Ir Cp*

Scheme 34. Proposed mechanism.

Chiba reported the synthesis of phenanthridine by copper-catalyzed C–N bond formation.88a,c They initially found that copper-catalyzed reaction of ethyl 2-azido-2-(biphenyl-2yl)acetate afforded the phenanthridine product likely through an iminyl copper species (Scheme 35, eq. 1).88b An alternative pathway to phenanthridines was also established from 2cyanobiphenyls (Scheme 35, eq. 2).88c The reaction of 2-cyanobiphenyl with Grignard reagent afforded the corresponding imine, from which the key iminyl copper species could be generated in the presence of copper salt under aerobic conditions, and the corresponding phenanthridines were produced in a similar fashion.


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ACS Catalysis

N N+ N–

Cu(OAc)2 (20 mol%) K 2CO 3 (1 equiv) OEt

N

Cu OEt

DMF, 60 °C O2 (1 atm)

O

C

N

+

N

OEt

O

O 50%

46% (1) R–MgBr (2) MeOH C

N

N

H

Cu(OAc)2 (10 mol%)

R

DMF, 80 °C

(1)

N

Cu

N

R

(2) R

O2 (1 atm)

Scheme 35. Phenanthridine synthesis from 2-cyanobiphenyls.

Maes reported interesting reaction of N-arylpyridin-2-amines that afforded pyrido[1,2a]benzimidazoles (Scheme 36, eq. 1).89a The reaction was applicable to 6-anilinopurine nucleosides (Scheme 36, eq. 2).89b R

R

Cu(OAc)2•H 2O (15–20 mol%) 3,4,5-trifluorobenzoic acid (15–20 mol%)

HN

(1)

N DMSO, 120 °C, O2

N

N

R Cu(OTf)2 (5 mol%)

HN N N

N

N

PhI(OAc) 2 (1.5 equiv) N

AcO O

R

AcOH/Ac2O, 80 °C, 2 h

N AcO O

N

(2)

N

OAc OAc

OAc OAc

Scheme 36. Copper-catalyzed synthesis of pyrido[1,2-a]benzimidazoles.


41

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3. C–H amination of arenes having a directing group 3-1. Amination with nitrene precursors Sanford reported a pioneering work on C–N bond-forming reaction of palladacycles derived from benzoquinoline by using iminoiodanes as nitrene precursors (Scheme 37).90a A DFT study on the Sanford’s transformation was performed by Cundari.90b The study showed that a Pd(IV) imido complex might be the key reactive intermediate during the reaction of the palladacycle with iminoindanes.

N Cl Pd Py

PhI=NTs THF, rt

N

Cl Pd Py NTs

HCl

N NHTs

Scheme 37. C–N bond formation from palladacycles.

Organic azides were widely employed as nitrogen sources91 such as sulfonyl,92-96 aryl,97 alkyl,98 acyl,99 phosphoryl,100 or silyl azides.101 Metal-catalyzed aromatic C–N amination reactions with organic azides have been extensively studied and the results are summarized in Table 7. Typically, catalyst-directing (coordinating) groups on the aromatic substrates are needed for the reaction to occur. Ruthenium, rhodium, and iridium complexes catalyze the intermolecular C–H amination with wide substrate scope. While cobalt catalysis is also known, the reaction is limited to N-pyrimidylindoles. Copper catalysts are suitable for the reaction of 2phenylpyridine derivatives. The proposed reaction mechanism is similar with that of Sanford’s work (Scheme 37): (1) formation of metallacycle, (2) generation of metal nitrenoid with


42

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ACS Catalysis

liberation of dinitrogen, (3) C–N bond formation, and (4) protonation of metal amido intermediate to liberate the product (Scheme 38). DG H NR

DG H Mtl

(4) protonation

(1) formation of metallacycle DG

DG Mtl NR

Mtl

(2) generation of metal-nitrenoid

(3) C–N bond formation DG

RN 3

Mtl NR –N2

Scheme 38. Reaction mechanism of directing group-assisted C–H amination with organic azides.


43

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Table 7. Metal-catalyzed aromatic C–H amination with organic azides. Ref. No. (R of subst.) O

Ru

Co

Rh

Ir

92a,b (SO2R’)

97a (Ar) 98 (Alkyl)

95a (SO2R’) 99a (COR’) 100 (PO(OR’)2)

92a,c,e,f (SO2R’) 99a (COR’)

98 (Alkyl)

100 (PO(OR’)2)

NR' 2

Cu

NHR

Z O NHR O

95c (SO2R’)

OH NHR Z Y

92h (SO2R’)

95a (SO2R’) 99a (COR’)

O NHR + R N – O NHR R2 P O

95d (SO2R’)

95b (SO2R’)

NHR Z

N

92a,d,g (SO2R’) 99b (COR’)

NHR

92a,g (SO2R) Z Het

N

93a (SO2R’) 93b (PO(OAr)2)

94a,c-f (SO2R’) 97a-c (Ar) 98 (Alkyl) 94b (SO2R’) 97a (Ar)

95a (SO2R’) 99a (COR’) 100 (PO(OR’)2) 101 (H)

96 (SO2R’)

NHR


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ACS Catalysis

3-2. Amination with amines having a leaving group on nitrogen Directing-group-assisted aromatic C–H amination can be achieved by a series of activated nitrogen source such as N-fluorobenznesulfonimide (NFSI),102 N-chloroamine,103 diphenylphthalimide-iodane,104 hydroxylamines (or substituted hydroxylamine),105 or N-hydroxy (or N-acetoxy)carbamates106 (Table 8). Very recently, Chang has developed a 1,4,2-dioxazol-5-one and its derivatives as a novel type of amidating reagent in C–H amination chemistry (Scheme 39).107 The proposed mechanism is as follows. Rhodium catalyst might exists as the equilibrium between A (reactive state) and A’ (resting state). Amidating reagent R coordinates to A to give B. Intermediate C is formed with generation of CO2, which ensures thermodynamic driving force of this elementary step. Ligand exchange of C with 2-phenylpyridine gives the corresponding product. Notably, nitrosobenzene was utilized as an aminating reagent of 2-phenylpyridine derivatives under rhodium catalysis.108


45

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Table 8. Metal-catalyzed C–H amination of arenes having a directing group. Ref. No. (Catalyst)

F–N(SO2Ph)2

O

Cl–NR’2

PhI-(NPhth)2

103a,b (Rh) NR' 2

RO–NR’2

RO–NR’COR”

105a (Pd) 105f (Ru)

106e (Ru)

NR 2

105g (Pd)

NHTf NR 2 O

103d (Rh)

105h (Pd)

OH NR 2 Z Y

102a (Pd)

106a (Pd)

O NR 2

103c (Fe)

O N H NR 2

N

103e (Rh)

+ N – O NR 2

102b (Rh) Z

N

103a (Rh)

104 (Cu mediated)

105b-e (Rh)

106b (Ir) 106c (Rh) 106d (Co)

NR 2


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ACS Catalysis

[Cp*RhCl 2]2 (1 mol%) N O

+

N

R

H

AgNTf2 (4 mol%)

O

N

ClCH2CH2Cl 40 °C, 12 h

O

+

CO2

NH R

O

[Proposed Mechanism] Me

Me Me N

Rh

N

Me Me

Me Me

N

X–

NH R

Me Me Me X– Rh N Ph

O

A'

A

N O R

N

O

O R

H

Me Me N

Me

Me Me

Me Me Rh O N

N

Me Me Me Rh N O

R

R

C

O

O

B

CO2

Scheme 39. Rhodium-catalyzed amidation with new amidating reagent.

Several Pd/norbornene-catalyzed Catellani-type109 C–H amination reactions were reported (Table 9).110 The three component reactions could install amine moiety into the orthoposition and electrophiles into the ipso position of halide substituent simultaneously (Scheme 40).


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Table 9. Pd/norbornene-catalyzed Catellani-type C–H amination reactions. cat. Pd

R X

+

BzO

N R2

R1

+

cat. norbornene

E+

R E N R2

H

R1

X = Br or I

E

Reagent (E+)

H

iPrOH CO2R 3

Dong110a Chen110b

CO2R 3

Ar

Ar–Bpin

Chen110c

Bpin

pinB–Bpin

Ritter110d

R3

R3

Chen and Wu110e

R3

Gu110f

HO

R3 HO 2C R3

R3

Xu and Liang110g

TsHNN


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ACS Catalysis

R R

E N R2

X

R1

H

Pd(0)

E+ R

R PdOBz N R2

PdX

R1

H

R

R

N R2

R1

PdOBz Pd

BzO

N R2

R1

Scheme 40. Reaction mechanism.

3-3. Amination with non-activated amine A series of early examples on directed C–H amination of 2-phenylpyridines with amides or anilines have been reported in 2006.111 Due to the catalyst-directing nature of pyridyl group, amino groups are introduced at the ortho-positions of benzene rings. Yu (J.-Q.) reported a copper-mediated reaction with tosyl amides under O2 atmosphere (Scheme 41, eq. 1).111a Chatani


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Page 50 of 86

developed copper-mediated C–H amination of 2-phenylpyridine (Scheme 41, eq. 2).111b The reaction could use aniline derivatives as a nitrogen source. Yu (W.-Y.) and Chen reported palladium-catalyzed reaction with amide (Scheme 41, eq. 3).111c The reaction was applicable not only to sp2-C–H bond but also a variety of sp3-C–H bond assisted with the coordination by nitrogen. After these findings, many C–H amination reactions were reported utilizing copper,112 iridium,113a,b palladium,113c rhodium,113d or nickel113e as a catalyst. Combinations of nitrogen sources with substrates are summarized in Table 10.

N H

+

H 2N

Cu(OAc)2 (1 equiv) Ts

H

+

H N

MeCN, 130 °C, 24 h air

N H 2N

N Ts

N

Cu(OAc)2 (2.4 equiv) Ar

(1)

H N

mesitylene, 160 °C, 2 h

(2) Ar

Pd(OAc) 2 (5 mol%) N H

+

H 2N

R O

K 2S2O8 (5 equiv) ClCH2CH2Cl

N H N

80 °C, 14–20 h

R

(3)

O

Scheme 41. Early examples on directed ortho-C–H-amination with non-activated amines.


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ACS Catalysis

Table 10. Metal-catalyzed C–H amination of arenes having a directing group. Ref. No. (Catalyst) Z

H–NHSO2R’ H–NHCOR’ 112a (Cu) 113d (Rh)

N

H–NPhth 112b,c (Cu)

H–NR’SO2R” H–NR’COR” 112c,h (Cu)

H–N=SOR’R”

H–NR’R”

112d (Cu mediated)

NR 2

112e (Cu) 113e (Ni)

O N H NR 2

N

112f (Cu)

O N H NR 2 N

O

112f (Cu)

O Het

N H NR 2 N

O

113a,b (Ir)

O NHAlk NR 2

113c (Pd) O NR 2 H N

112g,i (Cu) N

O NR 2 Het +N – O

112j (Cu)

112j,k (Cu)

NR 2


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Tan reported a copper-mediated ortho-nitration of benzamides in assistance with 8aminoquinoline as a directing group (Scheme 42).114a Unlike classical aromatic nitration using nitric acid, this reaction occurred at the ortho-position of amide group. Employment of readily available and easy-to-handle sodium nitrate improved the versatility of the reaction. Similarly, palladium- or rhodium-catalyzed ortho-nitration reactions were reported.114b,c Cu(OAc)2•H 2O (1.5 equiv)

O +

N H

K 2HPO 4 (2 equiv) NaNO 2

N

H 1 equiv

O N H NO 2

MeOH, 60 °C, 8 h

N

3 equiv

Scheme 42. Cu-mediated, directed ortho-nitration of benzamides.

Copper-catalyzed C–H azidation would be important transformation to install azide group, which has a high reactivity toward various reactions.115 Jiao has developed copper-catalyzed C– H azidation of anilines (Scheme 43).115a This is a rare example that simple amino group acts as a directing group. Importantly, this reaction occurred only at the ortho-position and no parasubstituted products were obtained when para-unsubstituted compounds were used as substrates. CuBr (10 mol%)

Me NH 2 Me

tBuOOH (2 equiv) +

TMSN 3

MeCN, 30 °C, Ar

H 1 equiv

NH 2 N3

2 equiv

Scheme 43. Cu-catalyzed ortho-azidation of anilines.


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ACS Catalysis

Dimerization of benzisoxazolones116a and carbazoles116b were reported, in which the C–H amination proceeded at the ortho-position of amino group. Patureau then developed crossreactions via ruthenium-catalyzed CDC amination to obtain N-(2-carbazolylaryl)-N-arylamines (Scheme 44).116c The reaction does not require a conventional, strongly coordinating directing group, and O2 can be used as oxidant.

H

N H

Ar

+

H N

[{(p-cymene)RuCl2}2] (5 mol%) Cu(OAc)2 (2.2 equiv) p-cymene/C2Cl 4/AcOH

N

N H

Ar

140-150 °C, 24 h

3 equiv

1 equiv

O2 or air

Scheme 44. CDC coupling of diarylamines and carbazoles.

4. C–H amination of simple arenes with excess amount While significant progress has been made to achieve aromatic C–H amination reactions, serious limitation still exists in the scope of applicable aromatic compounds. Due to a general difficulty in acquiring reactivity, a multitude of reported reactions are applicable only to aromatic compounds having catalyst-coordinating groups or that are electronically activated. Thus, the development of C–H amination reactions and catalysts for simple arenes has been a difficult task in the field. In this section, intermolecular C–H amination reactions of simple arenes (with excess amount) are summarized.

4-1. Amination with nitrene precursors


53

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Page 54 of 86

The first example of nitrene insertion into C–H bond of unsubstituted benzene was reported by Pérez using TpBr3Cu(NCMe) as a catalyst (Scheme 45).117 Although the reaction required benzene as the solvent, they proved that C–H bond of simple arenes could be amidated. He et al. reported gold-catalyzed reaction of mesitylene derivatives.117c They proposed that the reaction of mesitylene with electrophilic gold(III) chloride affords the corresponding aryl-gold intermediates, which reacts with PhI=NNs to give the amidated product. Recently, uncatalyzed C–H amidation proceeded when electron-rich arenes were mixed with sulfonyl azides at high temperatures.118 H

+ Solvent

PhI

N

TpBr3Cu(NCMe) (5 mol%)

NTs

Br

B

Br

Br N N

N N

Br

PhI

Br

N N

H

+

40% at rt 80% at 85 °C

Br

1 equiv

Ts

Br Br

Br

TpBr3

Scheme 45. Copper-catalyzed amidation of simple arenes.


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ACS Catalysis

4-2. Amination with amines having a leaving group on nitrogen Nicholas reported copper-catalyzed C–H amidation of simple arenes with Ntosyloxycarbamates (Table 11).119 They successfully converted various mono-substituted benzene derivatives. The regioselectivity is somewhat similar to those of typical aromatic electrophilic substitution reactions. The reactions preferentially occurred at the electron-rich positions, but the reaction at the ortho-position was completely suppressed when bulky tertbutylbenzene was used as a substrate. Table 11. Copper-catalyzed C–H amidation of simple arenes. [Cu(MeCN) 4]PF6 (20 mol%)

R

+

TsO

H N

O

R

neocuproine (20 mol%)

CCl 3

H N

140 °C

O

O

CCl 3

O

1 equiv

Solvent

N

N

neocuproine

[Scope of reaction] Me

Et

H N

O

tBu

H N

CCl 3

O

H N

CCl 3

O

CCl 3

O

O

O

59% (o/m/p = 2.4:1:1.1)

44% not determined

36% (o/m/p = 0:1.9:1)

Cl

CF 3

OMe

H N

O

CCl 3

H N

O

CCl 3

H N

O

CCl 3

O

O

O

51% (o/m/p = 5.6:1:3.4)

63% (o/m/p = 1.1:1.3:1)

20% (o/m/p = 1:2:0.5)


55

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Sanford reported visible light photo-catalyzed C−H amination of simple arenes at room temperature.120 The key step of this reaction is the formation of phthalimidyl radical from Nacyloxyphthalimide promoted by iridium-based photo-catalyst. Both simple arenes and heteroarenens are compatible in this radical amination protocol (Table 12.). Moderate to high ortho/para selectivity was observed with arenes bearing electron-donating substituents, while a modest meta selectivity was observed for arenes with electron-withdrawing substituents. Notably, C3-amination product was formed selectively when pyridine derivatives was used as a substrate. Table 12. Iridium-based, photo-catalytic C–H imidation of arenes with N-acyloxyphthalimide. O Ar H

O

O

F 3C

+

Ir(ppy) 3 (5 mol%)

O N

Ar N

MeCN, rt, 24 h O

10 equiv

O

visible light

1 equiv


N-radical from acyloxyphthalimides O

O

O

F 3C

O

Ir(ppy) 3

O N

visible light

F 3C

O

N

+

O

O

OMe

CF 3

NPhth

NPhth

NPhth

76%

O

23% (o/m/p = 1:8.4:2.8) O

O

51%

81% (o/m/p = 12.0:1.0:10.3)

45%

N

NPhth

69%

NPhth

NPhth NPhth

N

S

79% (α/β = 4.6:1)

N

N

NPhth

α NPhth β

NPhth N

57% (o/m = 1: >20)

N

66%

Br

N

Br

32%


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ACS Catalysis

Lee reported similar iridium-based photo-catalytic C–H imidation by using Nchlorophthalimides as nitrogen sources. In this case, they could reduce the amount of arenes to 2 equiv (Scheme 46).121

H

+ Cl

t-BuOCl, t-BuOH N

N

K 2CO 3, MeCN, rt visible light

R O

2 equiv

R O

1 equiv F

[Examples of substrate scope] O

Me

O

fac-Ir(dFppy) 3 (0.5 mol%)

O

MeO

N

F N

O F

N

O

O

46% (o/m/p = 2.5:1:1.3)

41% (o/m/p = 15:1:13)

F

IrIII N

N

F

F

fac-Ir(dFppy) 3

Scheme 46. Iridium-based, photo-catalytic C–H imidation with N-chlorophthalimide. A visible-light-promoted, catalyst-free C–H amidation of arenes using N-bromosaccharin as a nitrogen source was disclosed (Scheme 47).122 The substrate scope was wide enough to cover benzene, haloarenes, naphthalenes, pyrroles, thiophenes, and furans. The reactions were mainly regioselective at the most electron-rich position when electronically biased substrates were employed. O

O H

+

Br

N

R O

3 equiv

O

O

S

S

N

CH2Cl2, rt visible light

R O

1 equiv


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Scheme 47. Visible-light-promoted aromatic C–H imidation. 4-3. Amination with non-activated amine Chang reported a metal-free protocols for intermolecular C–N imidation of arenes using PhI(OAc)2 as an oxidant.123 Significantly, Chang’s protocol could control chemoselectivity in the amination (imidation) between aryl sp2 and benzylic sp3 C–H bonds by the choice of nitrogen sources; phthalimide reacted at aromatic sp2 C–H bonds and dibenzenesulfonimide reacted at benzylic sp3 C–H bonds (Scheme 48). DeBoef described amination of simple arenes using phthalimide as nitrogen source.124 The reaction proceeded chemoselectively at Csp2–H bonds. O H N

O

O H CH 3

PhI(OAc) 2

140-160 °C

N

aryl Csp2 –H

Me O

benzylic Csp

3 –H

SO2Ph H N

N(SO 2Ph) 2

SO2Ph

Scheme 48. Imide-controlled selective C–H imidation. After these pioneering works on uncatalyzed imidation with phthalimide, reports on the use of transition-metal catalysts to improve the regioselectivity have appeared (Table 13). Hartwig found the addition of palladium catalyst dramatically changed the regioselectivity.125 The selectivity was controlled by the sterics: imidation occurred at the 5-position of 1,2,3trimethylbenzene. DeBoef attained the para-selective C–H imidation by using gold(I) catalyst.126


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ACS Catalysis

Table 13. Imidation of mono-substituted arenes with phthalimide. O

Me

+

H N O

catalyst

Me

PhI(OAc) 2 PhthN

catalyst

regioselectivity

No catalyst

o/m/p mixture

Chang123 DeBoef124

Pd(OAc)2

m/p mixture

Hartwig125

Cy3PAuCl

para selective

DeBoef126

Antonchick improved their previous work83a to expand the substrate scope in the organocatalyzed aromatic C–H amidation reaction (Scheme 49).127 A catalytic amount of aryl iodide was used in the presence of stoichiometric amount of peracetic acid. The reaction proceeded at the ortho/para-positions of mono-substituted benzene derivatives. The mechanism is shown in Scheme 50: (1) hypervalent iodine (III) species A is generated in situ, (2) A undergoes ligand substitution to generate B, (3) nitrenium ion is formed to regenerate C. The electron-deficient nitrenium ion is attacked by arenes to provide the corresponding aminated products.


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organocat. (10 mol%) AcOOH (2.2 equiv) CF 3CO2H (5 equiv)

O R2

+

H

R1

N Z

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ClCH2CH2Cl rt, 0.6-4 h

N R1 Z o/p selective

1 equiv Z = OMe, NPhth

20 equiv

O

R2

organocat. I

I

Scheme 49. Organocatalytic approach toward C–H amidation of simple arenes.

O R1

N

X

F 3COCO O I I

-H +

AcOOH CF 3COOH

I

I

O R1

R2

N

X C

nitrenium ion

AcOH

organocat.

R2 R1

O X

N

O I

I

F 3COCO

OCOCF3

B X = OMe, NPhth

O I

I

OCOCF3

A O

CF 3CO2H R1

N H

X

Scheme 50. Proposed mechanism. 5. C–H amination of simple arenes as the limiting reagents Due to their low reactivity, aromatic C–H amination of simple arenes as the limiting reagents is very difficult. Recently, transition-metal-catalyzed radical approaches have enabled to


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functionalize 1 equiv of arene with various imides.128 In this final section, cutting-edge examples of such processes are summarized. 5-1. Amination with amines having a leaving group on nitrogen Ritter reported that catalytic C–H imidation of simple arenes can be achieved by using NFSI as a nitrogen source (Table 14).129 A synthetically useful reaction with arenes as limiting reagents was enabled by an N-oxide-ligated palladium catalyst and Ag(bipy)2ClO4 as the cocatalyst. NFSI transfers sulfonimidyl radical to substrates, and the importance of silver-mediated single electron transfer was proposed. This reaction was compatible for a diversity of arenes including pyrroles and thiophenes at or below ambient temperature. Moreover, each substrate was used as limiting reagent in 1 equivalent.


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Table 14. Pd/Ag-catalyzed aromatic C–H imidation. Pd cat. (5 mol%)

+

Ar H

1 equiv

SO2Ph N F SO2Ph

Ag(bipy)2ClO4 (10 mol%)

NFSI 2 equiv

23 °C, 24 h

Ar N(SO 2Ph) 2

MeCN

27 examples 45-99% O N

N Pd

N

N O

(OTf) 2

Pd cat.

F MeO 2C

N(SO 2Ph) 2 TMS

N(SO 2Ph) 2

OMe

Br

99%

Me

N(SO 2Ph) 2

A B

C

Br 45% A/B/C = 12:1:4

81%

O

NC

S

N(SO 2Ph) 2

Me

N Me O

84%

N(SO 2Ph) 2

N(SO 2Ph) 2 Cl

O Me Me

52%

75% Fenofibrate

O O

Me Me

Baran developed ferrocene-catalyzed aromatic C−H imidation with N-succinimidyl perester (NSP) as the precursor of an imidyl radical.130 The reaction installed succinimidyl group to arenes or heteroarenes with good regioselectivity at the electron-rich positions (Table 15). Relatively electron-rich arenes were applicable and the substrates bearing sensitive functional groups including halogen, ketone, and ester reacted without the loss of functional groups. The


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ferrocene catalyst likely plays the role of an electron shuttle to generate imidyl radical from NSP via an outer-sphere single electron transfer (Scheme 51). Table 15. Ferrocene-catalyzed aromatic C–H imidation.

O

+

R

O

O

O O

O

Cp2Fe (5 mol%) N

N

R

CH2Cl2, 50 °C, 2–7 h

Me Me

O

O

1 equiv

3 equiv

O

N

Me

O MeO

55%

N

Me S

N

O

N

O OMe

O tBu

N

O α S

O

44%

tBu

I

N

N

N O

O

50%

Br

β N Et

O

44%

α /β = 2.5:1

α /β = 6:1

O Me

N O

44%

58%

O

α EtO 2C

O

MeO

40%

β Br

O OMe

N

75%

N Me

O

O N

Me

23 examples 30-82%

4N O

O

N Me

Me O N N N O

30%


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Me O Me N (tBu)O 3C O

O

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O

[-tBuO -, -CO2, -acetone]

N

+ e-

O

FeII

FeIII OtBu

O N

H O N

- H +, - e-

O

O

Scheme 51. Proposed mechanism. Itami developed a facile and versatile C–H imidation of simple arenes using NFSI in the presence of copper bromide and 6,6’-dimethylbipyridine as catalyst and ligand, respectively (Table 16).131 The dimethyl groups on the ligand at 6,6’-positions play a crucial role for accelerating the reaction. Although the mechanism is not fully disclosed, an electrophilic imidyl radical was assumed as a reactive intermediate. This reaction was applicable to a wide variety of arenes including polycyclic aromatic hydrocarbons, heteroaromatics, porphyrins, and natural products.


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Table 16. Copper-catalyzed aromatic C–H imidation. CuBr (10 mol%)

H

+

func-Ar

func-Ar

ClCH2CH2Cl 70 °C, 12 h

NFSI 1.05-2 equiv

1 equiv

N(SO 2Ph) 2

6,6'-Me2bpy (12 mol%)

SO2Ph N F SO2Ph

23 examples 23-85% N

N

Me

Me

6,6'-Me2bpy N(SO 2Ph) 2

R1

N(SO 2Ph) 2

N(SO 2Ph) 2

N(SO 2Ph) 2

R1

47%

R1 = H 45% R1 = tBu 63%

38% tBu

S

Me tBu

S

O

N(SO 2Ph) 2 Br

58%

N H N

OMe

H N

N 47%

OMe

O

Me N

N Me

N

N

N(SO 2Ph) 2

caffeine

61%

N

O

N(SO 2Ph) 2

N(SO 2Ph) 2

N Cl

30%

N(SO 2Ph) 2

tBu

O tBu

59%

flavone 78%

Very recently, Nicewicz reported that photoredox catalyst can promote site-selective C– H amination reaction of arenes with azoles (Table 17.).132 They utilized 9-mesityl-10methylacridinium salt133 as a photoredox catalyst. A high para-selectivity of alkoxybenzenes was


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observed, and a variety of simple and complex aromatics underwent site-selective amination with azoles. Table 17. Photoredox catalyzed C–H amination of arenes with azoles.

+ H

R

1 equiv

HN Z Z Z 1.25-2.0 equiv

Me

Catalyst (5 mol%) TEMPO (20 mol%) Me

ClCH2CH2Cl, 20–72 h O2, 33 °C 455 nm LEDs

RO

R

Me

N Z Z Z

MeO

N

N N

OMe

Ph

R = OMe: 88% (o/p = 1:8.8) R = OTBS: 74% (o/p = 1:7.8) R = OPh: 86% (o/p = 1:11)

Hex N

Hex

N

N N

O 43%

45%

Et N

N N N 57% (o: p = 1:3)

N

O

O

+

HO N

N

MeO

BF 4

Catalyst

O

N N

tBu

N

tBu

39 examples 26-99%

NH CF 3CO2 – H

O

HO N 26%

53%

As clearly seen in the recent examples shown in this section, nitrogen-based radicals manifest significant advantage in decreasing the amount of simple arenes as the limiting reagent and broadening the applicability of aromatic C–H amination. Although most of these processes are considered to be an outer-sphere C–H amination, further mechanistic studies are awaited to understand and to generalize nitrogen radical-mediated C–H amination.


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5. Summary This review summarized the recent advances in the direct aromatic C–H amination powered by catalysis. Various nitrogen sources for C–H amination have been developed and introduced during this campaign. Transformations of 5-membered heteroaromatics and arenes having a directing group have been extensively studied that most of amine moieties and substrates can now be convertible under suitable conditions. The established studies provided us more information to approach the new frontier of catalytic aromatic C–H amination of unreactive, simple arenes as well as complex functional aromatics. However, the reaction of simple arenes are still difficult and there is plenty of room for improvement toward ideal C–H amination reaction. In fact, strongly electron-withdrawing substituents are required on the nitrogen when C–H amination of simple arenes is performed, which required additional steps to access functional molecules, for example, listed in Figure 1. Therefore, a C–H amination operating under mild conditions with high functional group compatibility and broader scope of both arenes and amines is needed for practitioners such as medicinal chemists and material chemists so that the discovery of functional molecules can be accelerated by late-stage C–H amination approach.

AUTHOR INFORMATION Corresponding Author * [email protected]. Author Contributions The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript.


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Notes The authors declare no competing financial interest. ACKNOWLEDGMENT This work was supported by the ERATO program from JST (K.I.), a Grant-in-Aid from JSPS (15K17821 to K.M.), and the Takeda Pharmaceutical Company Award in Synthetic Organic Chemistry, Japan (K.M.). ITbM is supported by the World Premier International Research Center (WPI) Initiative, Japan.

REFERENCES 1.

Selected reviews on natural products having arylamine structures: (a) Kim, J.; Movassaghi, M. Acc. Chem. Res. 2015, 48, 1159–1171. (b) Okano, K.; Tokuyama, H.; Fukuyama, T. Chem. Commun. 2014, 50, 13650–13663. (c) Evano, G.; Blanchard, N.; Toumi, M. Chem. Rev. 2008, 108, 3054–3131. (d) Evano, G.; Theunissen, C.; Pradal, A. Nat. Prod. Rep. 2013, 30, 1467–1489.

2.

Selected reviews on bioactive compounds and pharmaceuticals having arylamine structures: (a) Quintas-Cardama, A.; Cortes, J. Clin. Cancer Res. 2008, 14, 4392–4399. (b) QuintasCardama, A.; Kantarijian, H.; Cortes, J. Nat. Rev. Drug Discovery 2007, 6, 834–848. (c) Fisher, C.; Koenig, B. Beilstein J. Org. Chem. 2011, 7, 59–74. (d) Bikker, J. A.; Brooijmans, N.; Wissner, A.; Mansour, T. S. J. Med. Chem. 2009, 52, 1493–1509. (e) Hili, R.; Yudin, A. K. Nat. Chem. Biol. 2006, 2, 284–287.

3.

Uno, S.; Kamiya, M.; Yoshihara, T.; Sugawara, K.; Okabe, K.; Tarhan, M. C.; Fujita, H.; Funatsu, T.; Okada, Y.; Tobita, S.; Urano, Y. Nat. Chem. 2014, 6, 681–689.


68

Page 69 of 86

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4.

Selected reviews and examples on organic materials having arylamine structures: (a) Wakamiya, A.; Nishimura, H.; Fukushima, T.; Suzuki, F.; Saeki, A.; Seki, S.; Osaka, I.; Sasamori, T.; Murata, M.; Murata, Y.; Kaji, H. Angew. Chem., Int. Ed. 2014, 53, 5800– 5804. (b) Walzer, K.; Maennig, B.; Pfeiffer, M.; Leo, K. Chem. Rev. 2007, 107, 1233–1271. (c) Li, L.-L.; Diau, E. W.-G. Chem. Soc. Rev. 2013, 42, 291–304. (d) Shirota, Y.; Kageyama, H. Chem. Rev. 2007, 107, 953–1010. (e) Lee, M. M.; Teuscher, J.; Miyasaka, T.; Murakami, T. N.; Snaith, H. J. Science 2012, 338, 643–647. (f) Yella, A.; Lee, H.-W.; Tsao, H. N.; Yi, C.; Chandiran, A. K.; Nazeeruddin, M.; Diau, E. W.-G.; Yeh, C.-Y.; Zakeeruddin, S. M.; Grätzel, M. Science 2011, 334, 629–634. (g) Surry, D. S.; Buchwald, S. L. Chem. Sci. 2011, 2, 27–50.

5.

Ullmann, F. Ber. Dtsch. Chem. Ges. 1903, 36, 2382–2384.

6.

Kosugi, M.; Kameyama, M.; Migita, T. Chem. Lett. 1983, 12, 927–928.

7.

Guram, A. S.; Buchwald, S. L. J. Am. Chem. Soc. 1994, 116, 7901–7902.

8.

Paul, F.; Patt, J.; Hartwig, J. F. J. Am. Chem. Soc. 1994, 116, 5969–5970.

9.

Recent reviews: (a) Hartwig, J. F. Acc. Chem. Res. 2008, 41, 1534–1544. (b) Magano, J.; Dunetz, J. R. Chem. Rev. 2011, 111, 2177–2250. (c) Valente, C.; Çalimsiz, S.; Hoi, K. H.; Mallik, D.; Sayah, M.; Organ, M. G. Angew. Chem., Int. Ed. 2012, 51, 3314–3332. (d) Valente, C.; Pompeo, M.; Sayah, M.; Organ, M. G. Org. Proc. Res. Dev. 2014, 18, 180– 190. (e) Torborg, C.; Beller, M. Adv. Synth. Catal. 2009, 351, 3027–3043. (f) Rauws, T. R. M.; Maes, B. U. W. Chem. Soc. Rev. 2012, 41, 2463–2497. (g) Beletskaya, I. P.; Cheprakov, A. V. Organometallics 2012, 31, 7753–7808. (h) Monnier, F.; Taillefer, M. Angew. Chem., Int. Ed. 2009, 48, 6954–6971. (i) Fortman, G. C.; Nolan, S. P. Chem. Soc. Rev. 2011, 40, 5151–5169. (j) Surry, D. S.; Buchwald, S. L. Angew. Chem., Int. Ed. 2008,


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47, 6338–6361. Recent books: (k) Hartwig, J. Organotransition Metal Chemistry; University Science Books: Mill Valley, 2010; Chapter 8. (l) Jiang, L.; Buchwald, S. L. In Metal-Catalyzed Cross-Coupling Reactions, 2nd ed.; de Meijere, A.; Diederich, F. Ed; Wiley-VCH: Weinheim, 2004; Chapter 13. (m) Nishihara, Y. Applied Cross-Coupling Reactions; Springer, 2013. 10. Very selected recent examples: (a) Suzuki, Y.; Fukui, N.; Murakami, K.; Yorimitsu, H.; Osuka, A. Asian J. Org. Chem. 2013, 2, 1066–1071. (b) Ge, S.; Green, R. A.; Hartwig, J. F. J. Am. Chem. Soc. 2014, 136, 1617–1627. (c) Su, M.; Hoshiya, N.; Buchwald, S. L. Org. Lett. 2014, 16, 832–835. (d) Hatakeyama, T.; Imayoshi, R.; Yoshimoto, Y.; Ghorai, S.; Jin, M.; Takaya, H.; Norisuye, K.; Sohrin, Y.; Nakamura, M. J. Am. Chem. Soc. 2012, 134, 20262–20265. 11. Booth, G. In Nitro Compounds, Aromatic; Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005; Chapter 2. 12. Also see recent reviews on C–H amination: (a) Louillat, M.-L.; Patureau, F. W. Chem. Soc. Rev. 2014, 43, 901–910. (b) Cho, S. H.; Kim, J. Y.; Kwak, J.; Chang, S. Chem. Soc. Rev. 2011, 40, 5068–5083. (c) Subramanian, P.; Rudolf, G. C.; Kaliappan, K. P. Chem. Asian J. Early view. doi: 10.1002/asia.201500361. (d) Wan, J.-P.; Jing, Y. Beilstein J. Org. Chem. 2015, 11, 2209–2222. 13. Chen, Z.; Wang, B.; Zhang, J.; Yu, W.; Liu, Z.; Zhang, Y. Org. Chem. Front. 2015, 2, 1107–1295. 14. (a) Lwowski, W. Nitrenes; Interscience: New York, 1970. (b) Moody, C. J. In Comprehensive Organic Synthesis; Trost, B. M., Fleming, I., Eds.; Pergamon Press: Oxford, 1991; Vol. 6, p. 21. (c) Dauban, P., Dodd, R. H. In Amino Group Chemistry, From


70

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Synthesis to the Life Sciences; Ricci, A., Ed.: Wiley-VCH: Weinheim, 2008, p. 55. (d) Scriven, E.; Turnbull, K. Chem. Rev. 1988, 88, 297–368. 15. (a) Dauban, P.; Dodd, R. H. Synlett 2003, 1571–1586. (b) Yamada, Y.; Yamamoto, T.; Okawara, M. Chem. Lett. 1975, 4, 361–362. 16. Selected recent reviews: (a) Collet, F.; Dodd, R.; Dauban, P. Chem. Commun. 2009, 5061– 5074. (b) Ramirez, T.; Zhao, B.; Shi, Y. Chem. Soc. Rev. 2011, 41, 931–942. (c) Intrieri, D.; Zardi, P.; Caselli, A.; Gallo, E. Chem. Commun. 2014, 50, 11440–11453. (d) Dequirez, G.; Pons, V.; Dauban, P. Angew. Chem., Int. Ed. 2012, 51, 7384–7395. (e) Roizen, J. L.; Harvey, M. E.; Du Bois, J. Acc. Chem. Res. 2012, 45, 911–922. (f) Gephart III, R. T.; Warren, T. H. Organometallics 2012, 31, 7728–7752. (g) Shin, K.; Kim, H.; Chang, S. Acc. Chem. Res. 2015, 48, 1040–1052. (h) Che, C.-M.; Lo, V.; Zhou, C.-Y.; Huang, J.-S. Chem. Soc. Rev. 2011, 40, 1950–1975. (i) Jeffrey, J. L.; Sarpong, R. Chem. Sci. 2013, 4, 4092– 4106. (j) Davies, H. M. L.; Manning, J. R. Nature 2008, 451, 417–424. 17. Early examples of sp3 C–H amination: (a) Breslow, D. S.; Sloan, M. F. Tetrahedron Lett. 1968, 5349–5352. (b) Breslow, R.; Gellman, S. H. J. Chem. Soc. Chem. Commun. 1982, 1400–1401. (c) Breslow, R.; Gellmann, S. H. J. Am. Chem. Soc. 1983, 105, 6728–6729. (d) Nägeli, I.; Baud, C.; Bernardinelli, G.; Jacquier, Y.; Moran, M.; Müllet, P. Helv. Chim. Acta 1997, 80, 1087–1105. (e) Espino, C. G.; Du Bois, J. Angew. Chem., Int. Ed. 2001, 40, 598–600. 18. He, L.; Chan, P. W. H.; Tsui, W. M.; Yu, W. Y.; Che, C. M. Org. Lett. 2004, 6, 2405–2408. 19. Wei, J.; Xiao, W.; Zhou, C. Y.; Che, C. M. Chem. Commun. 2014, 50, 3373–3376. 20. Brachet, E.; Ghosh, T.; Ghosh, I.; König, B. Chem. Sci. 2015, 6, 987–992. 21. Kawano, T.; Hirano, K.; Satoh, T.; Miura, M. J. Am. Chem. Soc. 2010, 132, 6900–6901.


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22. (a) Matsuda, N.; Hirano, K.; Satoh, T.; Miura, M. Org. Lett. 2011, 13, 2860–2863. (b) Yotphan, S.; Beukeaw, D.; Reutrakul, V. Tetrahedron 2013, 69, 6627–6633. (c) Li, G.; Jia, C.; Sun, K.; Lv, Y.; Zhao, F.; Zhou, K.; Wu, H. Org. Biomol. Chem. 2015, 13, 3207–3210. 23. Liu, X. Y.; Gao, P.; Shen, Y. W.; Liang, Y. M. Org. Lett. 2011, 13, 4196–4199. 24. Sabat, N.; Klečka, M.; Slavĕtínská, L.; Klepetářová, B.; Hocek, M. RSC Adv. 2014, 4, 62140–62143. 25. John, A.; Nicholas, K. M. Organometallics 2012, 31, 7914–7920. 26. (a) McDonald, S. L.; Hendrick, C. E.; Wang, Q. Angew. Chem., Int. Ed. 2014, 53, 4667– 4670. (b) Yoon, H.; Lee, Y. J. Org. Chem. 2015, 80, 10244–10251. 27. (a) Sibbald, P. A.; Michael, F. E. Org. Lett. 2009, 11, 1147–1149. (b) Sibbald, P. A.; Rosewall, C. F.; Swartz, R. D.; Michael, F. E. J. Am. Chem. Soc. 2009, 131, 15945–15951. (c) Qiu, S. F.; Xu, T.; Zhou, J.; Guo, Y. L.; Liu, G. S. J. Am. Chem. Soc. 2010, 132, 2856– 2857. (d) Xiong, T.; Li, Y.; Lv, Y.; Zhang, Q. Chem. Commun. 2010, 46, 6831–6833. (e) Muñiz, K.; Kirsch, J.; Chav́ ez, P. Adv. Synth. Catal. 2011, 353, 689–694. (f) Iglesias, Á.; Álvarez, R.; Muñiz, K. Angew. Chem., Int. Ed. 2012, 51, 2225–2228. (g) Xiong, T.; Li, Y.; Mao, L.; Zhang, Q. Chem. Commun. 2012, 48, 2246–2248. (h) Trenner, J.; Depken, C.; Weber, T.; Breder, A. Angew. Chem., Int. Ed. 2013, 52, 8952–8956. 28. Wang, S. C.; Ni, Z. Q.; Huang, X.; Wang, J. C.; Pan, Y. J. Org. Lett. 2014, 16, 5648–5651. 29. Cecere, G.; König, C. M.; Alleva, J. L.; MacMillan, D. W. C. J. Am. Chem. Soc. 2013, 135, 11521–11524. 30. Qin, Q.; Yu, S. Org. Lett. 2014, 16, 3504–3507. 31. Wang, J.-D.; Liu, Y.-X.; Xue, D.; Wang, C.; Xiao, J. Synlett 2014, 25, 201–204. 32. Cho, S. H.; Kim, J. Y.; Lee, S. Y.; Chang, S. Angew. Chem., Int. Ed. 2009, 48, 9127–9130.


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33. Wang, J.; Hou, J. T.; Wen, J.; Zhang, J.; Yu, X. Q. Chem. Commun. 2011, 47, 3652. 34. Wang, R.; Liu, H.; Yue, L.; Zhang X.-K.; Tan, Q.-Y.; Pan, R.-L. Tetrahedron Lett. 2014, 55, 2233–2237. 35. Chen, S.; Zheng, K.; Chen, F. Tetrahedron Lett. 2012, 53, 6297–6299. 36. Wang, Q.; Schreiber, S. L. Org. Lett. 2009, 11, 5178–5180. 37. (a) Monguchi, D.; Fujiwara, T.; Furukawa, H.; Mori, A. Org. Lett. 2009, 11, 1607–1610. (b) Mitsuda, S.; Fujiwara, T.; Kimigafukuro, K.; Monguchi, D.; Mori, A. Tetrahedron 2012, 68, 3585–3590. 38. Zhao, H.; Wang, M.; Su, W.; Hong, M. Adv. Synth. Catal. 2010, 352, 1301–1306. 39. (a) Yu, H.; Dannenberg, C. A.; Li, Z.; Bolm, C. Chem. Asian J. 2015, Early view: doi:10.1002/asia.201500875. (b) Zhu, C.; Yi, M.; Wei, D.; Chen, X.; Wu, Y.; Cui, Y. Org. Lett. 2014, 16, 1840-1843. (c) Sun, K.; Wang, X.; Liu, L.; Sun, J.; Liu, X.; Li, Z.; Zhang, Z.; Zhang, G. ACS Catal. 2015, 5, 7194–7198. (d) Miyasaka, M.; Hirano, K.; Satoh, T.; Kowalczyk, R.; Bolm, C.; Miura, M. Org. Lett. 2010, 13, 359–361. 40. Oda, Y.; Hirano, K.; Satoh, T.; Miura, M. Org. Lett. 2012, 14, 664–667. 41. Xu, J.; Li, J.; Wei, Z.; Zhang, Q.; Shi, D. RSC Adv. 2013, 3, 9622–9624. 42. Guo, S.; Qian, B.; Xie, Y.; Xia, C.; Huang, H. Org. Lett. 2011, 13, 522–525. 43. Kim, J. Y.; Cho, S. H.; Joseph, J.; Chang, S. Angew. Chem., Int. Ed. 2010, 49, 9899–9903. 44. Wang, X.; Sun, K.; Lv, Y. H.; Ma, F. J.; Li, G.; Li, D. H.; Zhu, Z. H.; Jiang, Y. Q.; Zhao, F. Chem. Asian J. 2014, 9, 3413–3416. 45. Li, Y.; Liu, J.; Xie, Y.; Zhang, R.; Jin, K.; Wang, X.; Duan, C. Org. Biomol. Chem. 2012, 10, 3715–3720.


73

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 74 of 86

46. Pal, P.; Giri, A. K.; Singh, H.; Ghosh, S. C.; Panda, A. B. Chem. Asian J. 2014, 9, 2392– 2396. 47. (a) Froehr, T.; Sindlinger, C. P.; Kloeckner, U.; Finkbeiner, P.; Nachtsheim, B. J. Org. Lett. 2011, 13, 3754–3757. (b) Kloeckner, U.; Weckenmann, N. M.; Nachtsheim, B. J. Synlett 2012, 97–100. (c) Wagh, Y. S.; Sawant, D. N.; Bhanage, B. M. Tetrahedron Lett. 2012, 53, 3482–3485. (d) Lamani, M.; Prabhu, K. R. J. Org. Chem. 2011, 76, 7938–7944. (e) Beukeaw, D.; Udomsasporn, K.; Yotphan, S. J. Org. Chem. 2015, 80, 3447–3454. (f) Cai, Z.-J.; Wang, S.-Y.; Ji, S.-J. Org. Lett. 2013, 15, 5226–5229. 48. (a) Joseph, J.; Kim, J. Y.; Chang, S. Chem. Eur. J. 2011, 17, 8294–8298. (b) Wertz, S.; Kodama, S.; Studer, A. Angew. Chem., Int. Ed. 2011, 50, 1151–11515. (c) Xu, D.; Wang, W.; Miao, C.; Zhang, Q.; Xia, C.; Sun, W. Green Chem. 2013, 15, 2975–2980. (d) Wagh, Y. S.; Tiwari, N. J.; Bhanage, B. M. Tetrahedron Lett. 2012, 54, 1290–1293. (e) Wang, X.; Xu, D.; Miao, C.; Zhang, Q.; Sun, W. Org. Biomol. Chem. 2014, 12, 3108–3113. 49. (a) Yotphan, S.; Beukeaw, D.; Reutrakul, V. Synthesis 2013, 45, 936–942. (b) Sherry, B.; Chen, Y.-C.; Mangion, I.; Yin, J. Tetrahedron Lett. 2012, 53, 730–732. 50. (a) Li, Y.-X.; Ji, K.-G.; Wang, H.-X.; Ali, S.; Liang, Y.-M. J. Org. Chem. 2011, 76, 744– 747. (b) Li, Y.-X.; Wang, H.-X.; Ali, S.; Xia, X.-F.; Liang, Y.-M. Chem. Commun. 2012, 48, 2343–2345. 51. (a) Lubriks, D.; Sokolovs, I.; Suna, E. J. Am. Chem. Soc. 2012, 134, 15436–15442. (b) Sokolovs, I.; Lubriks, D.; Suna, E. J. Am. Chem. Soc. 2014, 136, 6920–6928. (c) Berzina, B.; Sokolovs, I.; Suna, E. ACS Catal. 2015, 5, 7008–7014. (d) Xiang, S.; Li, J.; Huang, H.;


74

Page 75 of 86

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Catalysis

Feng, C.; Ni, H.; Chen, X.; Wang, B.; Zhao, K.; Hu, P.; Redshaw, C. Adv. Synth. Catal. 2015, 357, 3435–3440. 52. (a) Yoshikai, N.; Wei, Y. Asian J. Org. Chem. 2013, 2, 466–478. (b) Mei, T. S.; Kou, L.; Ma, S.; Engle, K. M.; Yu, J.-Q. Synthesis 2012, 44, 1778–1791. (c) Yuan, J.; Liu, C.; Lei, A. Chem. Commun. 2014, 51, 1394–1409. 53. (a) Henn, L.; Hickey, D. M. B.; Moody, C. J.; Rees, C. W. J. Chem. Soc., Perkin Trans. 1 1984, 2189–2196. (b) Takeuchi, H.; Maeda, M.; Mitani, M.; Koyama, K. J. Chem. Soc., Chem. Commun. 1985, 287–289. 54. (a) Stokes, B. J.; Dong, H.; Leslie, B. E.; Pumphrey, A. L.; Driver, T. G. J. Am. Chem. Soc. 2007, 129, 7500–7501. (b) Shen, M.; Leslie, B. E.; Driver, T. G. Angew. Chem., Int. Ed. 2008, 47, 5056–5059. (c) Stokes, B. J.; Jovanović, B.; Dong, H. J.; Richert, K. J.; Riell, R. D.; Driver, T. G. J. Org. Chem. 2009, 74, 3225–3228. (d) Pumphrey, A. L.; Dong, H.; Driver, T. G. Angew. Chem., Int. Ed. 2012, 51, 5920–5923. (e) Stokes, B. J.; Driver, T. G. Eur. J. Org. Chem. 2011, 4071–4088. 55. (a) Dong, H.; Latka, R. T.; Driver, T. G. Org. Lett. 2011, 13, 2726–2729. (b) Shou, W. G.; Li, J.; Guo, T.; Lin, Z.; Jia, G. Organometallics 2009, 28, 6847–6854. (c) Ou, Y.; Jiao, N. Chem. Commun. 2013, 49, 3473–3475. 56. Chiba, S.; Zhang, L.; Sanjaya, S.; Ang, G. Y. Tetrahedron 2010, 66, 5692–5700. 57. (a) Isomura, K.; Kobayashi, S.; Taniguchi, H. Tetrahedron Lett. 1968, 9, 3499–3502. (b) Taber, D. F.; Tian, W. J. Am. Chem. Soc. 2006, 128, 1058–1059.


75

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 76 of 86

58. (a) Neber, P. W.; Burgard, A. Justus Liebigs Ann. Chem. 1932, 493, 281. (b) Neber, P. W.; Huh, G. Justus Liebigs Ann. Chem. 1935, 515, 283–296. 59. (a) Isomura, K.; Uto, K.; Taniguchi, H. J. Chem. Soc., Chem. Commun. 1977, 664–665. (b) Chiba, S.; Hattori, G.; Narasaka, K. Chem. Lett. 2007, 36, 52–53. (c) Jana, S.; Clements, M. D.; Sharp, B. K.; Zheng, N. Org. Lett. 2010, 12, 3736–3739. 60. (a) Pizzotti, M.; Cenini, S.; Quici, S.; Tollari, S. J. Chem. Soc., Perkin Trans. 2 1994, 913– 917. (b) Smitrovich, J. H.; Davies, I. W. Org. Lett. 2004, 6, 533–535. (c) Laronze-Cochard, M.; Cochard, F.; Daras, E.; Lansiaux, A.; Brassart, B.; Vanquelef, E.; Prost, E.; Nuzillard, J.-M.; Baldeyrou, B.; Goosens, J.-F.; Lozach, O.; Meijer, L.; Riou, J.-F.; Henon, E.; Sapi, J. Org. Biomol. Chem. 2010, 8, 4625–4636. 61. (a) Hsieh, T. H. H.; Dong, V. M. Tetrahedron 2009, 65, 3062–3068. (b) Ferretti, F.; ELAtawy, M. A.; Muto, S.; Hagar, M.; Gallo, E. Ragaini, F. Eur. J. Org. Chem. 2015, 5712– 5715. 62. Tan, Y. C.; Hartwig, J. F. J. Am. Chem. Soc. 2010, 132, 3676–3677. 63. (a) Deb, I.; Yoshikai, N. Org. Lett. 2013, 15, 4254. (b) Zhang, Z.; Li, J.; Zhang, G.; Ma, N.; Liu, Q.; Liu, T. J. Org. Chem. 2015 80, 6875. (c) Hazra, S.; Mondal, B.; Rahaman, H.; Roy, B. Eur. J. Org. Chem. 2014, 2806. (d) Chen, H.; Chiba, S. Org. Biomol. Chem. 2014, 12, 42. (e) Li, D.; Ma, H.; Yu, W. Adv. Synth. Catal. 2015, 357, 3696–3702. 64. For non-catalytic intramolecular annulation of O-acyloximes, see: (a) Alonso, R.; Campos, P. J.; Garcia, B.; Rodriguez, M. A. Org. Lett. 2006, 8, 3521–3523. (b) Alonso, R.; Caballero, A.; Campos, P. J.; Rodriguez, M. A. Tetrahedron 2010, 66, 8828–8831. (c)


76

Page 77 of 86

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Catalysis

Portela-Cubillo, F.; Scanlan, E. M.; Scott, J. S.; Walton, J. C. Chem. Commun. 2008, 4189– 4191. (d) Portela-Cubillo, F.; Lymer, J.; Scanlan, E. M.; Scott, J. S.; Walton, J. C. Tetrahedron 2008, 64, 11908–11916. (e) McBurney, R. T.; Slawin, A. M. Z.; Smart, L. A.; Yu, Y. P.; Walton, J. C. Chem. Commun. 2011, 47, 7974–7976. 65. Ramirez, T. A.; Wang, Q.; Zhu, Y.; Zheng, H.; Peng, X.; Cornwall, R. G.; Shi, Y. Org. Lett. 2013, 15, 4210–4213. 66. Zheng, H.; Zhu, Y.; Shi, Y. Angew. Chem., Int. Ed. 2014, 53, 11280–11284. 67. (a) Tsang, W. C. P.; Zheng, N.; Buchwald, S. L. J. Am. Chem. Soc. 2005, 127, 14560– 14561. (b) Tsang, W. C. P.; Munday, R. H.; Brasche, G.; Zheng, N.; Buchwald, S. L. J. Org. Chem. 2008, 73, 7603–7610. 68. Jordan-Hore, J. A.; Johansson, C. C. C.; Gulias, M.; Beck, E. M.; Gaunt, M. J. J. Am. Chem. Soc. 2008, 130, 16184–16186. 69. Sugahara, T.; Murakami, K.; Yorimitsu, H.; Osuka, A. Angew. Chem., Int. Ed. 2014, 53, 9329–9333. 70. (a) Youn, S. W.; Bihn, J. H.; Kim, B. S. Org. Lett. 2011, 13, 3738–3741. (b) Weinstein, A. B.; Stahl, S. S. Catal. Sci. Technol. 2014, 4, 4301–4307. (c) Mei, T. S.; Wang, X. S.; Yu, J.-Q. J. Am. Chem. Soc. 2009, 131, 10806–10807. 71. Yang, W. G.; Chen, J. X.; Huang, X. B.; Ding, J. C.; Liu, M. C.; Wu, H. Y. Org. Lett. 2014, 16, 5418–5421.


77

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 78 of 86

72. (a) Pearson, R.; Zhang, S. Y.; He, G.; Edwards, N.; Chen, G. Beilstein J. Org. Chem. 2013, 9, 891–899. (b) Zhao, G.; Chen, C.; Yue, Y.; Yu, Y.; Peng, J. J. Org. Chem. 2015, 80, 2827–2834. 73. Wang, G. W.; Yuan, T. T.; Li, D. D. Angew. Chem., Int. Ed. 2011, 50, 1380–1383. 74. Lee, D. J.; Yoo, E. J. Org. Lett. 2015, 17, 1830–1833. 75. (a) Haffemayer, B.; Gulias, M.; Gaunt, M. J. Chem. Sci. 2011, 2, 312–315. (b) Yang, M.; Jiang, X.; Shi, Z.-J. Org. Chem. Front. 2015, 2, 51–54. (c) Yang, M; Su, B; Wang, Y; Chen, K; Jiang, X; Zhang, Y.-F.; Zhang, X.-S.; Chen, G; Cheng, Y; Cao, Z; Guo, Q.-Y.; Wang, L.; Shi, Z.-J. Nat. Commun. 2014, 5, 4707. 76. (a) Kumar, R. K.; Ali, M. A.; Punniyamurthy, T. Org. Lett. 2011, 13, 2102–2105. For transition-metal-free conditions, see: (b) Zhou, Z.; Liu, Q.-L.; Zhu, Y.-M. Heterocycles 2011, 83, 2057–2065. 77. (a) Xiao, Q.; Wang, W.; Liu, G.; Meng, F.; Chen, J.; Yang, Z.; Shi, Z. Chem. Eur. J. 2009, 15, 7292–7296. (b) Kumar, R. K.; Punniyamurthy, T. RSC Adv. 2012, 2, 4616–4619. 78. Wasa, M.; Yu, J. Q. J. Am. Chem. Soc. 2008, 130, 14058–14059. 79. (a) Inamoto, K.; Saito, T.; Hiroya, K.; Doi, T. J. Org. Chem. 2010, 75, 3900–3903. (b) Inamoto, K.; Kawasaki, J.; Hiroya, K.; Kondo, Y.; Doi, T. Chem. Commun. 2012, 48, 4332–4334. 80. (a) Inamoto, K.; Saito, T.; Katsuno, M.; Sakamoto, T.; Hiroya, K. Org. Lett. 2007, 9, 2931– –2934. (b) Cyr, P.; Régnier, S.; Bechara, W. S.; Charette, A. B. Org. Lett. 2015, 17, 3386– 3389. (c) Wang, H.-Y.; Liu, X.-C.; Huang, Z.-B.; Shi, D.-Q. J. Heterocyclic Chem. 2015, 52, 380–385.


78

Page 79 of 86

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Catalysis

81. (a) Wang, X. Q.; Jin, Y. H.; Zhao, Y. F.; Zhu, L.; Fu, H. Org. Lett. 2012, 14, 452–455. (b) Zhou, W.; Liu, Y.; Yang, Y. Q.; Deng, G. J. Chem. Commun. 2012, 48, 10678–10680. (c) Huang, J. B.; Wan, C. Q.; Xu, M. F.; Zhu, Q. Eur. J. Org. Chem. 2013, 1876–1880. (d) Selvaraju, M.; Sun, C. M. Adv. Synth. Catal. 2014, 356, 1329–1336. (e) Li, X.; He, L.; Chen, H.; Wu, W.; Jiang, H. J. Org. Chem. 2013, 78, 3636–3646. (f) Kielesiński, L.; Tasior, M.; Gryko, D. T. Org. Chem. Front. 2015, 2, 21–28. (g) Cho, S. H.; Yoon, J.; Chang, S. J. Am. Chem. Soc. 2011, 133, 5996–6005. 82. (a) Zhang, T. S.; Bao, W. L. J. Org. Chem. 2013, 78, 1317–1322. (b) Karthikeyan, I.; Sekar, G. Eur. J. Org. Chem. 2014, 8055–8063. (c) Aoki, Y.; Imayoshi, R.; Hatakeyama, T.; Takaya, H.; Nakamura, M. Heterocycles 2015, 90, 893–900. 83. (a) Antonchick, A. P.; Samanta, R.; Kulikov, K.; Lategahn, J. Angew. Chem., Int. Ed. 2011, 50, 8605–8608. (b) Chi, Y.; Zhang, W. X.; Xi, Z. F. Org. Lett. 2014, 16, 6274–6277. (c) Kashiwa, M.; Sonoda, M.; Tanimori, S. Eur. J. Org. Chem. 2014, 4720–4723. 84. (a) He, G.; Zhao, Y.; Zhang, S.; Lu, C.; Chen, G. J. Am. Chem. Soc. 2012, 134, 3–6. (b) Nadres, E. T.; Daugulis, O. J. Am. Chem. Soc. 2012, 134, 7–10. (c) He, G.; Lu, C.; Zhao, Y.; Nack, W. A.; Chen, G. Org. Lett. 2012, 14, 2944–2947. (d) Zhang, D.; Gao, F.; Nian, Y.; Zhou, Y.; Jiang, H.; Liu, H. Chem. Commun. 2015, 51, 7509–7511. (e) Mei, T. S.; Leow, D. S.; Xiao, H.; Laforteza, B. N.; Yu, J.-Q. Org. Lett. 2013, 15, 3058–3061. (f) Wang, C.; Chen, C. P.; Zhang, J. Y.; Han, J.; Wang, Q.; Guo, K.; Liu, P.; Guan, M. Y.; Yao, Y. M.; Zhao, Y. S. Angew. Chem., Int. Ed. 2014, 53, 9884–9888. (g) Ye, X.; He, Z.; Ahmed, T.; Weise, K.; Akhmedov, N. G.; Petersen, J. L.; Shi, X. Chem. Sci. 2013, 4, 3712–3716.


79

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 80 of 86

85. (a) Takamatsu, K.; Hirano, K.; Satoh, T.; Miura, M. Org. Lett. 2014, 16, 2892–2895. (b) Takamatsu, K.; Hirano, K.; Satoh, T.; Miura, M. J. Org. Chem. 2015, 80, 3242–3249. 86. (a) Suzuki, C.; Hirano, K.; Satoh, T.; Miura, M. Org. Lett. 2015, 17, 1597–1600. (b) Jiang, Q.; Duan-Mu, D.; Zhong, W.; Chen, H.; Yan, H. Chem. Eur. J. 2013, 19, 1903–1907. 87. (a) Matsubara, S.; Asano, K.; Kajita, Y.; Yamamoto, M. Synthesis 2007, 2055–2059. (b) Yamamoto, M.; Matsubara, S. Chem. Lett. 2007, 36, 172–173. 88. (a) Chiba, S. Bull. Chem. Soc. Jpn. 2013, 86, 1400–1411. (b) Chiba, S.; Zhang, L.; Ang, G. Y.; Hui, B. W.-Q. Org. Lett. 2010, 12, 2052–2055. (c) Zhang, L.; Ang, G. Y.; Chiba, S. Org. Lett. 2010, 12, 3682–3685. 89. (a) Masters, K.-S.; Rauws, T. R. M.; Yadav, A. K.; Herrebout, W. A.; Van der Veken, B.; Maes, B. U. W. Chem. Eur. J. 2011, 17, 6315–6320. (b) Qu, G.-R.; Liang, L.; Niu, H.-Y.; Rao, W.-H.; Guo, H.-M.; Fossey, J. Org. Lett. 2012, 14, 4494–4497. 90. (a) Dick, A. R.; Remy, M. S.; Kampf, J. W.; Sanford, M. S. Organometallics 2007, 26, 1365–1370. (b) Ke, Z.; Cundari, T. R. Organometallics 2010, 29, 821–834. 91. Shin, K.; Kim, H.; Chang, S. Acc. Chem. Res. 2015, 48, 1040–1052. 92. Ruthenium-catalyzed amidation with sulfonyl azides: (a) Kim, J.; Kim, J.; Chang, S. Chem. Eur. J. 2013, 19, 7328–7333. (b) Yadav, M. R.; Rit, R. K.; Sahoo, A. K. Org. Lett. 2013, 15, 1638–1641. (c) Bhanuchadra, M.; Yadav, M. R.; Rit, R. K.; Kuram, M. R.; Sahoo, A. K. Chem. Commun. 2013, 49, 5225–5227. (d) Thirunavukkarasu, V. S.; Raghuvanshi, K.; Ackermann, L. Org. Lett. 2013, 15, 3286–3289. (e) Shin, Y.; Han, S.; De, U.; Park, J.; Sharma, S.; Kumar Mishra, N.; Lee, E. K.; Lee, Y.; Kim, H. S.; Kim, I. S. J. Org. Chem. 2014, 79, 9262–9271. (f) Zhang, L.-L.; Li, L.-H.; Wang, Y.-Q.; Yang, Y.-F.; Liu, X.-Y.; Liang, Y.-M. Organometallics 2014, 33, 1905–1908. (g) Zhou, X.; Luo, P.; Long, L.;


80

Page 81 of 86

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Catalysis

Ouyang, M.; Sang, X.; Ding, Q. Tetrahedron 2014, 70, 6742–6748. (h) Pan, C.; Abdukader, A.; Han, J.; Cheng, Y.; Zhu, C. Chem. Eur. J. 2014, 20, 3606–3609. 93. Cobalt-catalyzed amidation with sulfonyl azides: Sun, B.; Yoshino, T.; Matsunaga, S.; Kanai, M. Adv. Synth. Catal. 2014, 356, 1491–1495. With phosphoryl azide: Sun, B.; Yoshino, T.; Matsunaga, S.; Kanai, M. Chem. Commun. 2015, 51, 4659–4661. 94. Rhodium-catalyzed amidation with sulfonyl azides: (a) Kim, J. Y.; Park, S. H.; Ryu, J.; Cho, S. H.; Kim, S. H.; Chang, S. J. Am. Chem. Soc. 2012, 134, 9110–9113. (b) Shi, J.; Zhou, B.; Yang, Y.; Li, Y. Org. Biomol. Chem. 2012, 10, 8953–8955. (c) Yu, D. G.; Suri, M.; Glorius, F. J. Am. Chem. Soc. 2013, 135, 8802–8805. (d) Park, S. H.; Kwak, J.; Shin, K.; Ryu, J.; Park, Y.; Chang, S. J. Am. Chem. Soc. 2014, 136, 2492–2502. (e) Xia, X. F.; Han, J. J. Org. Chem. 2014, 79, 4180–4185. (f) Zhang, C.; Zhou, Y.; Deng, Z.; Chen, X.; Peng, Y. Eur. J. Org. Chem. 2015, 1735–1744. 95. Iridium-catalyzed amidation with sulfonyl azides: (a) Lee, D.; Kim, Y.; Chang, S. J. Org. Chem. 2013, 78, 11102–11109. (b) Gwon, D.; Lee, D.; Kim, J.; Park, S.; Chang, S. Chem. Eur. J. 2014, 20, 12421–12425. (c) Lee, D.; Chang, S. Chem. Eur. J. 2015, 21, 5364. (d) Pi, C.; Cui, X.; Wu, Y. J. Org. Chem. 2015, 80, 7333–7339. 96. Copper-catalyzed amidation with sulfonyl azides: Peng, J.; Xie, Z.; Chen, M.; Wang, J.; Zhu, Q. Org. Lett. 2014, 16, 4702–4705. 97. Amination with aryl azide: (a) Ryu, J.; Shin, K.; Park, S. H.; Kim J. Y.; Chang, S. Angew. Chem., Int. Ed. 2012, 51, 9904–9908. (b) Kim, H. J.; Ajitha, M. J.; Lee, Y.; Ryu, J.; Kim, J.; Lee, Y.; Jung, Y.; Chang, S. J. Am. Chem. Soc. 2014, 136, 1132–1140. (c) Tang, C. H.; Yuan, Y. Z.; Cui, Y. X.; Jiao, N. Eur. J. Org. Chem. 2013, 7480–7483.


81

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 82 of 86

98. Amination with alkyl azide: Shin, K.; Baek, Y.; Chang, S. Angew. Chem., Int. Ed. 2013, 52, 8031–8036. 99. Amination with acyl azide: (a) Ryu, J.; Kwak, J.; Shin, K.; Lee, D.; Chang, S. J. Am. Chem. Soc. 2013, 135, 12861–12868. (b) Shin, K.; Ryu, J.; Chang, S. Org. Lett. 2014, 16, 2022– 2025. 100. Amidation with phosphoryl azides: Kim, H.; Park, J.; Kim, J.; Chang, S. Org. Lett. 2014, 16, 5466–5469. 101. Copper-mediated amination with silyl azide: Peng, J.; Chen, M.; Xie, A.; Luo, S.; Zhu, Q. Org. Chem. Front. 2014, 1, 777–781. 102. (a) Sun, K.; Li, Y.; Xiong, T.; Zhang, J. P.; Zhang, Q. J. Am. Chem. Soc. 2011, 133, 1694– 1697. (b) Tang, R. J.; Luo, C. P.; Yang, L.; Li, C.-J. Adv. Synth. Catal. 2013, 355, 869–873. 103. (a) Ng, K. H.; Zhou, Z. Y.; Yu, W. Y. Org. Lett. 2012, 14, 272–275. (b) Grohmann, C.; Wang, H.; Glorius, F. Org. Lett. 2014, 14, 656–659. (c) Matsubara, T.; Asako, S.; Ilies, L.; Nakamura, E. J. Am. Chem. Soc. 2014, 136, 646–649. (d) Ng, F.-N.; Zhou, Z.; Yu, W.-Y. Chem. Eur. J. 2014, 20, 4474–4480. (e) Gwon, D.; Hwang, H.; Kim, H. K.; Marder S. R.; Chang, S. Chem. Eur. J. 2015, 21, 17200–17204. 104. Kantak, A. A.; Marchetti, L.; DeBoef, B. Chem. Commun. 2015, 51, 3574–3577. 105. (a) Yoo, E. J.; Ma, S.; Mei, T. S.; Chan, K. S. L.; Yu, J.-Q. J. Am. Chem. Soc. 2011, 133, 7652–7655. (b) Yu, S.; Wan, B.; Li, X. Org. Lett. 2013, 15, 3706–3709. (c) Wu, K.; Fan, Z. L.; Xue, Y.; Yao, Q. Z.; Zhang, A. Org. Lett. 2014, 16, 42–45. (d) Xue, Y.; Fan, Z. L.; Jiang, X. L.; Wu, K.; Wang, M. N.; Ding, C. Y.; Yao, Q. Z.; Zhang, A. Eur. J. Org. Chem. 2014, 7481–7488. (e) Zhou, B.; Du, J. J.; Yang, Y. X.; Feng, H. J.; Li, Y. C. Org. Lett. 2014, 16, 592–595. (f) Shang, M.; Zeng, S.-H.; Sun, S.-Z.; Dai, H.-X.; Yu, J.-Q. Org. Lett.


82

Page 83 of 86

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Catalysis

2013, 15, 5286–5289. (g) Zhu, D.; Yang, G.; He, J.; Chu, L.; Chen, G.; Gong, W.; Chen, K.; Eastgate, M. D.; Yu, J.-Q. Angew. Chem., Int. Ed. 2015, 54, 2497–2500. (h) Ng, K.-H.; Ng, F.-N.; Yu, W.-Y. Chem. Commun. 2012, 48, 11680–11682. 106. (a) Ng, K. H.; Chan, A. S. C.; Yu, W. Y. J. Am. Chem. Soc. 2010, 132, 12862–12864. (b) Patel, P.; Chang, S. Org. Lett. 2014, 16, 3328–3331. (c) Ali, M. A.; Yao, X. Y.; Sun, H.; Lu, H. J. Org. Lett. 2015, 17, 1513–1516. (d) Patel, P.; Chang, S. ACS Catal. 2015, 5, 853–858. (e) Yadav, M. R.; Shankar, M.; Ramesh, E.; Ghosh, K.; Sahoo, A. K. Org. Lett. 2015, 17, 1886–1889. 107. (a) Park, Y. Park, K. T.; Kim, J. G.; Chang, S. J. Am. Chem. Soc. 2015, 137, 4534–4542. (b) Park, Y.; Jee, S.; Kim, J. G.; Chang, S. Org. Proc. Res. Dev. 2015, 19, 1024–1029. (c) Park, J.; Chang, S. Angew. Chem., Int. Ed. 2015, 54, 14103–14107. 108. Du, J.; Yang, Y.; Feng, H.; Li, Y.; Zhou, B. Chem. Eur. J. 2014, 20, 5727. 109. For reviews of Catellani reaction, see: (a) Catellani, M. Top. Organomet. Chem. 2005, 14, 21–53. (b) Martins, A.; Mariampillai, B.; Lautens, M. Top. Curr. Chem. 2010, 292, 1–33. (c) Ferraccioli, R. Synthesis 2013, 45, 581–591. (d) Catellani, M.; Motti, E.; Della Ca’, N. Acc. Chem. Res. 2008, 41, 1512–1522. 110. (a) Dong, Z.; Dong, G. J. Am. Chem. Soc. 2013, 135, 18350–18353. (b) Chen, Z.-Y.; Ye, C.-Q.; Zhu, H.; Zeng, X.-P. Yuan, J.-J. Chem. Eur. J. 2014, 20, 4237–4241. (c) Ye, C. Q.; Zhu, H.; Chen, Z. Y. J. Org. Chem. 2014, 79, 8900–8905. (d) Shi, H.; Babinski, D. J.; Ritter T. J. Am. Chem. Soc., 2015, 137, 3775–3778. (e) Pan, S.; Ma, X.; Zhong, D.; Chen, W.; Liu, M.; Wu, H. Adv. Synth. Catal. 2015, 357, 3052–3056. (f) Sun, F.; Gu, Z. Org. Lett. 2015, 17, 2222−2225. (g) Zhou, P.-X.; Ye, Y.-Y.; Ma, J.-W.; Zheng, L.; Tang, Q.; Qiu, Y.F.; Song, B.; Qiu, Z.-H.; Xu, P.-F.; Liang, Y.-M. J. Org. Chem. 2014, 79, 6627–6633.


83

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 84 of 86

111. (a) Chen, X.; Hao, X.-S.; Goodhue, C. E.; Yu, J.-Q. J. Am. Chem. Soc. 2006, 128, 6790– 6791. (b) Uemura, T.; Imoto, S.; Chatani, N. Chem. Lett. 2006, 35, 842–843. (c) Thu, H. Y.; Yu, W. Y.; Che, C. M. J. Am. Chem. Soc. 2006, 128, 9048–9049. 112. (a) John, A.; Nicholas, K. M. J. Org. Chem. 2011, 76, 4158–4162. (b) Xu, H.; Qiao, X. X.; Yang, S. P.; Shen, Z. M. J. Org. Chem. 2014, 79, 4414–4422. (c) Li, G.; Jia, C.; Chen, Q.; Sun, K.; Zhao, F.; Wu, H.; Wang, Z.; Lv, Y.; Chen, X. Adv. Synth. Catal. 2015, 357, 1311– 1315. (d) Wang, L.; Priebbenow, D.; Dong, W.; Bolm, C. Org. Lett. 2014, 16, 2661–2663. (e) Tran, L. D.; Roane, J.; Daugulis, O. Angew. Chem., Int. Ed. 2013, 52, 6043–6046. (f) Shang, M.; Sun, S. Z.; Dai, H. X.; Yu, J.-Q. J. Am. Chem. Soc. 2014, 136, 3354–3357. (g) Martínez, Á. M.; Rodríguez, N.; Arrayás, R. G.; Carretero, J. Chem. Commun. 2014, 50, 2801–2803. (h) Shuai, Q.; Deng, G.; Chua, Z.; Bohle, D.; Li, C. Adv. Synth. Catal. 2010, 352, 632–636. (i) Li, Q.; Zhang, S.-Y.; He, G.; Ai, Z.; Nack, W.; Chen, G. Org. Lett. 2014, 16, 1764–1767. (j) Li, G.; Jia, C.; Sun, K. Org. Lett. 2013, 15, 5198–5201. (k) Zhu, J.; Kong, Y.; Lin, F.; Wang, B.; Chen, Z.; Liu, L. Eur. J. Org. Chem. 2015, 1507–1515. 113. (a) Kim, H.; Shin, K.; Chang, S. J. Am. Chem. Soc. 2014, 136, 5904–5907. (b) Kim, H.; Chang, S. ACS Catal. 2015, 5, 6665–6669. (c) Xiao, B.; Gong, T. J.; Xu, J.; Liu, Z. J.; Liu, L. J. Am. Chem. Soc. 2011, 133, 1466–1474. (d) Zhao, H. Q.; Shang, Y. P.; Su, W. P. Org. Lett. 2013, 15, 5106–5109. (e) Yan, Q. Q.; Chen, Z. K.; Yu, W. L.; Yin, H.; Liu, Z. X.; Zhang, Y. H. Org. Lett. 2015, 17, 2482–2485. 114. (a) Liu, J.; Zhuang, S.; Gui, Q.; Chen, X.; Yang, Z.; Tan, Z. Adv. Synth. Catal. 2015, 357, 732–738. (b) Qiao, H.-J.; Yang, F.; Wang, S.-H.; Leng, Y.-T.; Wu, Y.-J. Tetrahedron 2015, 71, 9258–9263. (c) Xie, F.; Qi, Z.; Li, X. Angew. Chem. Int. Ed. 2013, 52, 11862 –11866.


84

Page 85 of 86

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Catalysis

115. (a) Tang, C.; Jiao, N. J. Am. Chem. Soc. 2012, 134, 18924–18927. (b) Fan, Y.; Wan, W.; Ma, G.; Gao, W.; Jiang, H.; Zhu, S.; Hao, J. Chem. Commun. 2014, 50, 5733–5736. (c) Yao, B.; Liu, Y.; Zhao, L.; Wang, D.-X.; Wang, M.-X. J. Org. Chem. 2014, 79, 11139– 11145. 116. (a) Gao, X.-A.; Yan, R.-L.; Wang, X.-X.; Yan, H.; Li, J.; Guo, H.; Huang, G.-S. J. Org. Chem. 2012, 77, 7700–7705. (b) Louillat, M. L.; Patureau, F. W. Org. Lett. 2013, 15, 164– 167. (c) Louillat, M. L.; Biafora, A.; Legros, F.; Patureau, F. W. Angew. Chem., Int. Ed. 2014, 53, 3505–3509. 117. (a) Díaz-Requejo, M. M.; Belderrín, T. R.; Nicasio, M. C.; Trofimenko, S.; Pérez, P. J. J. Am. Chem. Soc. 2003, 125, 12078–12079. (b) Fructos, M. R.; Trofimenko, S.; DíazRequejo, M. M.; Pérez, P. J. J. Am. Chem. Soc. 2006, 128, 11784–11791. (c) Li, Z.; Capretto, D. A.; Rahaman, R. O.; He, C. J. Am. Chem. Soc. 2007, 129, 12058–12059. 118. Wang, L. G.; Borah, A. J.; Yan, G. B. Tetrahedron Lett. 2015, 56, 1353–1355. 119. John, A.; Byun, J.; Nicholas, K. M. Chem. Commun. 2013, 49, 10965. 120. Allen, L. J.; Cabrera, P. J.; Lee, M.; Sanford, M. S. J. Am. Chem. Soc. 2014, 136, 5607– 5610. 121. Kim, H.; Kim, T.; Lee, D. G.; Roh, S. W.; Lee, C. Chem. Commun. 2014, 50, 9273–9276. 122. Song, L.; Zhang, L.; Luo, S.; Cheng, J. Chem. Eur. J. 2014, 20, 14231–14234. 123. Kim, H. J.; Kim, J.; Cho, S. H.; Chang, S. J. Am. Chem. Soc. 2011, 133, 16382–16385. 124. Kantak, A. A.; Potavathri, S.; Barham, R. A.; Romano, K. M.; DeBoef, B. J. Am. Chem. Soc. 2011, 133, 19960–19965. 125. Shrestha, R.; Mukherjee, P.; Tan, Y.; Litman, Z. C.; Hartwig, J. F. J. Am. Chem. Soc. 2013, 135, 8480–8483.


85

ACS Catalysis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 86 of 86

126. Marchetti, L.; Kantak, A.; Davis, R.; DeBoef, B. Org. Lett. 2015, 17, 358–361. 127. Samanta, R.; Bauer, J. O.; Strohmann, C.; Antonchick, A. P. Org. Lett. 2012, 14, 5518– 5521. 128. Yoshida reported electrochemical approach toward C–H amination of arene as the limiting reagent: (a) Morofuji, T.; Shimizu, A.; Yoshida, J. J. Am. Chem. Soc. 2013, 135, 5000– 5003. (b) Morofuji, T.; Shimizu, A.; Yoshida, J. J. Am. Chem. Soc. 2014, 136, 4496–4499. (c) Morofuji, T.; Shimizu, A.; Yoshida, J. Chem. Eur. J. 2015, 21, 3211–3214. 129. Boursalian, G. B.; Ngai, M. Y.; Hojczyk, K. N.; Ritter, T. J. Am. Chem. Soc. 2013, 135, 13278–13281. 130. Foo, K.; Sella, E.; Thomé, I.; Eastgate, M. D.; Baran, P. S. J. Am. Chem. Soc. 2014, 136, 5279–5282. 131. Kawakami, T.; Murakami, K.; Itami, K. J. Am. Chem. Soc. 2015, 137, 2460–2463. 132. Romero, N. A.; Margrey, K. A.; Tay, N. E.; Nicewicz, D. A. Science 2015, 349, 1326– 1330. 133. Fukuzumi, S.; Kotani, H.; Ohkubo, K.; Ogo, S.; Tkachenko, N. V.; Lemmetyinen, H. J. Am. Chem. Soc. 2004, 126, 1600–1601.


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