Subscriber access provided by University of Florida | Smathers Libraries
Letter
Asymmetric Allylation of Furfural Derivatives: Synergistic Effect of Chiral Ligand and Organocatalyst on Stereochemical Control Yong-Liang Su, Zhi-Yong Han, Yu-Hui Li, and Liu-Zhu Gong ACS Catal., Just Accepted Manuscript • DOI: 10.1021/acscatal.7b02667 • Publication Date (Web): 18 Oct 2017 Downloaded from http://pubs.acs.org on October 18, 2017
Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
ACS Catalysis is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.
Page 1 of 6
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
Asymmetric Allylation of Furfural Derivatives: Synergistic Effect of Chiral Ligand and Organocatalyst on Stereochemical Control Yong-Liang Su †‡, Zhi-Yong Han †‡, Yu-Hui Li † and Liu-Zhu Gong*†‡ †
Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
‡
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
ABSTRACT: An asymmetric allylation reaction at the benzylic position of furfurals that are easily accessed from 5-HMF, a biomass derivative, has been established by palladium and amine cooperative catalysis. The high levels of enantioselectivity of up to 97% ee were enabled by the synergistic stereochemical control of a chiral TADDOL-based phosphoramidite ligand and a chiral diphenylprolinol silyl ether. The product could be feasibly transformed into chiral aryl-substituted spiroacetal by a four-step reaction sequence. KEYWORDS: Asymmetric cooperative catalysis • trienamine • palladium • asymmetric allylation • furfural
Trienamine catalysis1, pioneered by Jørgensen,2 Chen2,3 and Melchiorre,4 has provided an efficient approach to access asymmetric functionalization of C−H bonds distal to the formyl or keto group. The asymmetric transformations of this type involving furan derivatives are of particular interest and significance due to a diverse range of synthetically significant reactions capable of occurring at furan moiety, including hydrolysis,5 DielsAlder reactions,6 Achmatowicz reaction,7 and others.8 However, the trienamine-catalyzed asymmetric functionalization of furan derivatives appears to be quite limited. Melchiorre and coworkers reported an aminecatalyzed asymmetric Diels-Alder reaction of 3-(2methylfuranyl)acrylaldehyde, mediated by in situ formed heterocyclic ortho-quinodimethanes (Figure 1a).4 Chen created an asymmetric Friedel-Crafts alkylation reaction of 2-furfuryl ketones by trienamine catalysis (Figure 1b).9 5-Alkyl furfurals have been easily prepared from 5hydroxymethylfurfural (5-HMF),10 an industrial feedstock produced from biomass, including glucose or fructose.11 The stereoselective functionalization at the benzylic position of 5-alkyl furfurals basically leads to a family of synthetically significant chiral substances and is thereby greatly worthy to be developed. However, the stereochemical control holds great challenge due to the reaction site located distal to the chiral auxiliary of the amine catalyst (Figure 1c). Indeed, Albrecht recently attempted to establish an asymmetric Michael addition reaction of 2-alkyl furfurals to nitroalkenes by trienamine catalysis, only leading to moderate levels of enantioselectivity (52−80% ee, Scheme 1a).12 Recently, organo/metal cooperative catalysis has been convinced a robust strategy for the development of unprecedented
Figure 1. Trienamine catalysis enabled functionalization of furan derivatives
asymmetric
asymmetric transformations, which are basically unable to be realized by a single catalyst.13 Although the enamine/transition metal cooperative catalysis has been well explored,13a, 14 the trienamine catalysis combined with metal catalysis has been much less described. Thus far, only one example was reported by Jørgensen describing an asymmetric allylic alkylation of benzo-fused cyclic α, β-unsaturated aldehydes enabled by trienamine/ transition metal cooperative catalysis.15 Herein, we will present a highly enantioselective allylation at the benzylic posi-
ACS Paragon Plus Environment
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
tion of 5-alkyl furfurals by harnessing Pd/amine cooperative catalysis (Scheme 1b). The chiral amine and ligand synergistically act on the control of stereoselectivity to provide highly functionalized chiral furan derivatives with excellent yields and enantioselectivities.
Page 2 of 6
Table 1. Optimization of catalysts and reaction conditionsa O Ph
O
[Pd] (5 mol%) L (10 mol%) amine (20 mol%) Ph (PhO)2PO2H (20 mol%)
OH H
+
Ph
1a
Ph
Ph
2a
N H
Ar Ar OTMS
A1: Ar = Ph A2: Ar = 3,5-(CF3)2-C6H3 A3: Ar = 3,5-Me2-C6H3 A4: Ar = 2-naphthalenyl
Scheme 1. Asymmetric functionalization at the benzylic position of furfural derivatives.
The initial investigation was focused on the evaluation of chiral amines for the reaction of 5-benzylfurfural 1a with allylic alcohol 2a by using an achiral palladium complex as co-catalyst (Table 1). As anticipated, the desired reaction proceeded smoothly under the cooperative catalysis of 5 mol% of Pd(PPh3)4, 20 mol% of phosphoric acid and 20 mol% of diphenylprolinol silyl ether A1,1f to generate 3aa (after reduction with NaBH4) in 40% yield, but with only 60:40 diastereomeric ratio and low level of enantioselectivities for both diastereomers (Table 1, entry 1). The examination of different prolinol silyl ethers found that the amine structure has considerable effect on the reaction conversion, but exerted very little impact on stereoselectivity (entries 2−8), indicating that the chiral organocatalyst was unable to efficiently control the stereochemistry, alone. Relatively, the organocatalyst A8 turned out to be promising and delivered the highest yield, but still low enantioselectivity (entry 8). Thus, chiral ligands of palladium complexes were next investigated in collaboration with diphenylprolinol silyl ether A8. A number of chiral ligands commonly used for the palladium-catalyzed asymmetric allylic alkylations, previously, for instance, Trost ligands,16 17 phosphinooxazoline ligands and BINOL-derived phosphoramidites18, were unable to accelerate the desired reaction (See Supporting Information for details). To our delight, TADDOL-based phosphoramidite19 ligand L1 allowed the reaction to proceed smoothly, providing the product with 41% yield, 80:20 diastereomeric ratio and 94% ee for the major isomer (entry 9). Either the aryl substituents of TADDOL moiety or N-substituents of the phosphoramidite ligands significantly affected the catalytic activity of palladium complexes (entries 9−16). Among them, the ligand L8 offered the best results (entry 16). Switching the amine catalyst from A8 to simple
entry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17e 18f 19g 20h 21i
[Pd]/L
N H
A5: R = TES A6: R = TIPS A7: R = TBS A8: R = SiPh3
O
Ph Ph
O P N O
O O
O R1 P N R2 O Ph Ph
Ar Ar L1: Ar = Ph L2: Ar = 3,5-(CF3)2-C6H3 L3: Ar = 3,5-Me2-C6H3 L4: Ar = 4-Ph-C6H4
Amine
OH
3aa
Ar Ar O
Ph Ph OR
O
Ph
DCE, 35 oC NaBH4/MeOH workup
Yield (%)b 40 trace 19 27 47 38 43 56 41 trace 9 22 42 26 31 61 9 trace 8 83 99
L5: R1, R2 = (CH2)5 L6: R1 = R2 = i-Pr L7: R1 = Et, R2 = Ph L8: R1 = Et, R2 = i-Pr
drc
ee (%)d 4 (44) N.D. 6 (54) 3 (44) 5 (42) 8 (40) 5 (46) 11 (67) 94 (61) N.D. 90 (31) 92 (44) 93 (53) 93 (62) 93 (60) 94 (69) 79 (71) N.D. 93 (64) 94 (69) 94 (69)
Pd(PPh3)4 A1 60:40 Pd(PPh3)4 A2 N.D. Pd(PPh3)4 A3 60:40 Pd(PPh3)4 A4 60:40 Pd(PPh3)4 A5 60:40 A6 60:40 Pd(PPh3)4 Pd(PPh3)4 A7 60:40 Pd(PPh3)4 A8 60:40 Pd(dba)2/L1 A8 80:20 A8 N.D. Pd(dba)2/L2 Pd(dba)2/L3 A8 76:24 Pd(dba)2/L4 A8 77:23 Pd(dba)2/L5 A8 76:24 A8 80:20 Pd(dba)2/L6 Pd(dba)2/L7 A8 80:20 Pd(dba)2/L8 A8 82:18 Pd(dba)2/L8 pyrrolidine 60:40 Pd(dba)2/L8 A8 N.D. Pd(dba)2/L8 A8 N.D. Pd(dba)2/L8 A8 82:18 Pd(dba)2/L8 A8 83:17 Pd(dba)2/ A8 94 57:43 82 (92)j 22i ent-L8 a Reaction conditions: unless indicated otherwise, the reaction of 1a (0.20 mmol), 2a (0.40 mmol), [Pd] (0.01 mmol), ligand (0.02 mmol), amine (0.04 mmol), and (PhO)2POOH (0.04 mmol) was carried out in dichloroethane (0.2 M) for 36 h, followed by reduction with NaBH4 in MeOH at room temperature. bIsolated yield. c The d.r. was determined by 1H NMR analysis of the crude reaction mixture. dDetermined by chiral HPLC analysis; the ee of the minor product is shown in the brackets eThe reaction was carried out at 60 oC for 36 h. f o-Fluorobenzoic acid was used as the acid. g TsOH.H2O was used as the acid. hThe reaction was carried out in DCE (0.33 M) for 3 days. i The reaction was carried out in DCE (0.67 M) for 3 days. jOpposite enantiomers of both diastereomers were obtained. N.D. = Not Determined.
pyrrolidine resulted in a very sluggish reaction, giving the product with a rather poor yield and deminished stereoselectivity at an elevated reaction temperature and prolonged reaction time (entry 17). The acid additive was finally examined. The use of o-fluorobenzoic acid completely inhibited the reaction (entry 18). pToluenesulfonic acid allowed the reaction to give 8% yield
ACS Paragon Plus Environment
Page 3 of 6
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
with maintained enantiomeric excess (entry 19). Other acid additives tested were unable to improve the reaction performance (See Supporting Information for details) and the phosphoric acid turned out to be the best (entry 16). A much enhanced yield, 83:17 diastereomeric ratio and 94% ee for the major isomer were obtained by conducting the reaction at a higher concentration and prolonged time (entries 21 and 22). A relatively lower diastereoric ratio and enantioselectivity were delivered for the opposite enantiomer of 3a when the enantiomer of L8 (ent-L8) was exploited (entry 22), implying that the stereochemistry depends on the configuration of chiral ligand while chiral amine assists the stereochemical control.20 With the optimized reaction conditions in hand, the generality for 5-alkylfurfurals 1 was investigated by the reaction with allylic alcohol 2a (Table 2). Either of electron-donating, -withdrawing, or bulky substituents at the para position of benzene ring were nicely tolerated (entries 1−6), giving rise to corresponding products in excellent yields (88−>99%) and with excellent enantioselectivities for the major isomers (93-96% ee) and up to 85:15 diastereomeric ratios. Furfurals bearing 2naphthalenyl group or aryl groups with meta- or othosubstituents also underwent the reaction very cleanly and delivered excellent yields, good diastereoselectivity and high enantioselectivity (3ha−3la, entries 7−11).
enantioselectivities for the major diastereomer. The reaction of 5-ethylfurfural 1m with 2a proceeded at 60 oC for 5 days to furnish a product 3ma in 34% yield, 60:40 dr. and 92(82) % ee. Similarly, the furfural 1n provided 3na in 44% yield, 67: 33 dr. and 94% ee for the major diastereomer under the reoptimized reaction conditions.
The asymmetric allylic alkylation reaction of the furfural 1a was also applied to a variety of diaryl substitued allylic alcohols (Table 3). In general, various allylic alcohols bearing aromatic groups underwent the reaction smoothly to afford chiral furfural derivatives with excellent yields (90−>99%), high enantioselectivities (87−97% ee) and satisfactory diastereoselectivities (up to 87:13, entries 1−10). The enantioselectivity was found to be unbiased toward the electronic property of the substituents of the benzene ring of 2 (entries 1−5). Table 3. Substrate scope of allyllic alcoholsa
Table 2. Substrate scope of furfuralsa
drc yield ee (%)d b (%) 1 4-Me-C6H4 3ba 92 81:19 94 (70) 2 4-OMe-C6H4 3ca >99 83:17 94 (70) 3 4-tBu-C6H4 3da 95 85:15 95 (66) 4 4-F-C6H4 3ea >99 82:18 96 (65) 5 4-Cl-C6H4 3fa 94 81:19 95 (46) 6 4-CF3-C6H4 3ga 88 80:20 93 (76) 7 3-Me-C6H4 3ha >99 81:19 95 (69) 8 3-OMe-C6H4 3ia 94 82:18 93 (72) 3ja 93 80:20 91 (73) 9 3-F-C6H4 10 2-naphthyl 3ka >99 81:19 94 (71) 11 2-F-C6H4 3la >99 72:28 94 (74) a Reaction conditions: unless indicated otherwise, reactions of 1 (0.20 mmol), 2a (0.40 mmol), Pd(dba)2 (0.01 mmol), L8 (0.02 mmol), amine A8 (0.04 mmol), and (PhO)2POOH (0.04 mmol) were carried out in dichloroethane (0.67 M). After complete consumption of 1, the reaction mixture was treated with NaBH4 in MeOH at rt. bIsolated yield. cThe d.r. was determined by 1H NMR analysis of the crude reaction mixture. dEe of the major product, determined by chiral HPLC analysis; the ee of the minor product is shown in the brackets. Entry
Ar
3
Non-benzylic alkyl substituted furfurals were also examined (eq. 1). However, the substrates exhibited much lower reactivity but still resulted in excellent
Entry Ar 3 Yield (%)b drc ee (%)d 1 4-Me-C6H4 3ab 97 80:20 95 (64) 2 4-OMe-C6H4 3ac 90 80:20 88 (46) 3 4-F-C6H4 3ad 92 83:17 95 (72) 4 4-Cl-C6H4 3ae 92 83:17 96 (72) 5 4-CF3-C6H4 3af >99 82:18 97 (78) 6 3-Me-C6H4 3ag >99 83:17 95 (53) 7 3-OMe-C6H4 3ah >99 82:18 95 (63) 8 3-Cl-C6H4 3ai 91 87:13 95 (65) 9 2-naphthyl 3aj >99 82:18 94 (37) 10 1-naphthyl 3ak >99 70:30 87 (51) a Reaction conditions: unless indicated otherwise, reactions of 1a (0.20 mmol), 2 (0.40 mmol), Pd(dba)2 (0.01 mmol), L8 (0.02 mmol), amine A8 (0.04 mmol), and(PhO)2POOH (0.04 mmol) were carried out in dichloroethane (0.67 M). After complete consumption of 1, the reaction mixture was treated with NaBH4 in MeOH at rt. bIsolated yield. cThe d.r. was determined by 1H NMR analysis of the crude reaction mixture. dEe of the major product, determined by chiral HPLC analysis; the ee of the minor product is shown in the brackets.
To demonstrate the practicability of current reaction, a scale-up reaction of the furfural 1a (3.0 mmol) with the allylic alcohol 2a was performed under standard conditions (Scheme 2). The product 3aa was isolated in an almost quantitative yield and maintained diastereoselectivity (82:17) and enantioselectivity (94% ee) for the major product. Notably, the two diastereomers could be separated by flash column chromatography. The (S, S)-3aa was subjected to Sharpless asymmetric dihydroxylation reaction21 to afford diol 4aa as a diastereomeric mixture. The exposure of 4aa to NaIO4 at
ACS Paragon Plus Environment
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
room temperature generated the corresponding aldehyde, which was subsequently reduced with NaBH4 to afford alcohol 5aa. The diol 5aa was found capable of undergoing a cascade Achmatowicz rearrangement/spiroketalization process to furnish arylsubstitued spiroacetal.22 23 In this case, when 5aa was treated with Oxone/KBr, a 5/5 spiroacetal 6aa bearing a semiketal moiety rather than the 5/6 spirocyclic 7aa, was obtained, presumably due to that a neighboring group participated in the Achmatowicz rearrangement process. The structure and absolute configuration of the semiketal 6aa was assigned by X-ray crystallographic analysis of its single crystal. The configuration of the major isomer of compound 3 was thus assigned by analogy.
Scheme 2. Gram-scale reaction and synthetic application. In conclusion, we have developed a Pd/amine cooperatively catalyzed asymmetric allylation reaction at the benzylic positon of furfural derivatives. The synergistic effect of the chiral ligand of palladium catalyst and the chiral amine allowed the reaction to offer high levels of stereoselectivities. A diverse range of synthetically useful chiral furanyl methanol derivatives could be accessed in high enantioselectivities from easily available biomass-derived platform molecule, 5-HMF. More importantly, the cooperative catalysis of chiral palladium complex and chiral organocatalyst suggests a robust strategy for the control of stereoselectivity in asymmetric reactions that are unable to offer high enantioselectivity by chiral organocatalysts, alone.
ASSOCIATED CONTENT Supporting Information. Complete experimental procedures and characterization data for the prepared compounds. This material is available free of charge via the internet at http://pubs.acs.org
AUTHOR INFORMATION Corresponding Author *E-mail:
[email protected] Author Contributions ‡ S. Y. L. and H. Z. Y. contributed equally to this manuscript.
Page 4 of 6
ACKNOWLEDGMENT We are grateful for financial support from NSFC (Grants 21232007, 21502183) and Chinese Academy of Science (Grant No.XDB20000000).
REFERENCES (1) (a) Paz, B. M.; Jiang, H.; Jørgensen, K. A. Chem.- Eur. J. 2015, 21, 1846-1853. (b) Kumar, I.; Ramaraju, P.; Mir, N. A. Org. Biomol. Chem. 2013, 11, 709-716. (c) Jurberg, I. D.; Chatterjee, I.; Tannert, R.; Melchiorre, P. Chem. Commun. 2013, 49, 4869-4883. (d) Jiang, H.; Albrecht, L.; Jørgensen, K. A. Chem. Sci. 2013, 4, 2287-2300. (e) Li, J. L.; Liu, T. Y.; Chen, Y. C. Acc. Chem. Res. 2012, 45, 1491-1500. (f) Jensen, K. L.; Dickmeiss, G.; Jiang, H.; Albrecht, L.; Jørgensen, K. A. Acc. Chem. Res. 2012, 45, 248-264. (g) Arceo, E.; Melchiorre, P. Angew. Chem., Int. Ed. 2012, 51, 5290-5292. (2) Jia, Z. J.; Jiang, H.; Li, J. L.; Gschwend, B.; Li, Q. Z.; Yin, X. A.; Grouleff, J.; Chen, Y. C.; Jørgensen, K. A. J. Am. Chem. Soc. 2011, 133, 5053-5061. (3) Jia, Z. J.; Zhou, Q.; Zhou, Q. Q.; Chen, P. Q.; Chen, Y. C. Angew. Chem., Int. Ed. 2011, 50, 8638-8641. (4) Liu, Y.; Nappi, M.; Arceo, E.; Vera, S.; Melchiorre, P. J. Am. Chem. Soc. 2011, 133, 15212-15218. (5) (a) Nikbin, N.; Caratzoulas, S.; Vlachos, D. G. Chemsuschem 2013, 6, 2066-2068. (b) Williams, C. L.; Chang, C.C.; Do, P.; Nikbin, N.; Caratzoulas, S.; Vlachos, D. G.; Lobo, R. F.; Fan, W.; Dauenhauer, P. J. ACS Catal. 2012, 2, 935-939. (6) Oliver Kappe, C.; Shaun Murphree, S.; Padwa, A. Tetrahedron 1997, 53, 14179-14233. (7) (a) Achmatowicz, O.; Bukowski, P.; Szechner, B.; Zwierzchowska, Z.; Zamojski, A. Tetrahedron 1971, 27, 1973-1996. (b) Li, Z.; Tong, R. J. Org. Chem. 2016, 81, 4847-4855. (c) Plutschack, M. B.; Seeberger, P. H.; Gilmore, K. Org. Lett. 2017, 19, 30-33. (8) (a) Wright, D. L. Chemical Innovation 2001, 31, 17-21. (b) Craig, R. A., II; Stoltz, B. M. Chem. Rev. 2017, 117, 7878-7909. (9) (a) Li, J. L.; Yue, C. Z.; Chen, P. Q.; Xiao, Y. C.; Chen, Y. C. Angew. Chem., Int. Ed. 2014, 53, 5449-5452. (b) Yang, G.-J.; Du, W.; Chen, Y.-C. J. Org. Chem. 2016, 81, 10056-10061. (c) Xiao, B.X.; Du, W.; Chen, Y.-C. Adv. Synth. Catal. 2017, 359, 1018-1027. (10) Ryabukhin, D. S.; Zakusilo, D. N.; Kompanets, M. O.; A.Tarakanov, A.; Boyarskaya, I. A.; Artamonova, T. O.; Khohodorkovskiy, M. A.; Opeida, I. O.; Vasilyev, A. V. Beilstein J. Org. Chem. 2016, 12, 2125-2135. (11) (a) van Putten, R. J.; van der Waal, J. C.; de Jong, E.; Rasrendra, C. B.; Heeres, H. J.; de Vries, J. G. Chem. Rev. 2013, 113, 1499-1597. (b) Hoydonckx, H. E.; Van Rhijn, W. M.; Van Rhijn, W.; De Vos, D. E.; Jacobs, P. A. In Ullmann's Encyclopedia of Industrial Chemistry; Wiley-VCH Verlag GmbH & Co. KGaA: 2000. (12) Skrzyńska, A.; Przydacz, A.; Albrecht, Ł. Org. Lett. 2015, 17, 5682-5685. (13) (a) Afewerki, S.; Cordova, A. Chem. Rev. 2016, 116, 1351213570. (b) Inamdar, S. M.; Shinde, V. S.; Patil, N. T. Org. Biomol. Chem. 2015, 13, 8116-8162. (c) Chen, D. F.; Han, Z. Y.; Zhou, X. L.; Gong, L. Z. Acc. Chem. Res. 2014, 47, 2365-2377. (d) Allen, A. E.; MacMillan, D. W. C. Chem. Sci. 2012, 3, 633-658. (e) Du, Z. T.; Shao, Z. H. Chem. Soc. Rev. 2013, 42, 1337-1378. (f) Zhong, C.; Shi, X. Eur. J. Org. Chem. 2010, 2010, 2999-3025. (g) Shao, Z.; Zhang, H. Chem. Soc. Rev. 2009, 38, 2745-2755. (h) Han, Z. Y.; Wang, C.; Gong, L. Z. In Science of Synthesis: Asymmetric Organocatalysis; K. Maruoka, Ed.; Georg Thieme Verlag: Stuttgart, Germany, 2012; Vol. 2, p 697. (14) (a) Ibrahem, I.; Córdova, A. Angew. Chem., Int. Ed. 2006, 45, 1952-1956. (b) Bihelovic, I.; Matovic, R.; Vulovic,B.; Saicic, R. N. Org. Lett. 2007, 9, 5063-5066. (c) Zhou, H.; Zhang, L.; Xu, C.;
ACS Paragon Plus Environment
Page 5 of 6
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
Luo, S. Angew. Chem., Int. Ed. 2015, 54, 12645-12648. (d) Zhou, H.; Wang, Y.; Zhang, L.; Cai, M.; Luo, S. J. Am. Chem. Soc. 2017, 139, 3631-3634.. (15) Naesborg, L.; Halskov, K. S.; Tur, F.; Monsted, S. M. N.; Jørgensen, K. A. Angew. Chem., Int. Ed. 2015, 54, 10193-10197. (16) (a) Trost, B. M.; VanVranken, D. L. Chem. Rev. 1996, 96, 395-422 (b) Trost, B. M. Acc. Chem. Res. 1996, 29, 355-364. (17) (a) Helmchen, G.; Pfaltz, A. Acc. Chem. Res. 2000, 33, 336345. (b) Helmchen, G.; Kudis, S.; Sennhenn, P.; Steinhagen, H. Pure Appl. Chem. 1997, 69, 513-518. (c) Pfaltz, A. Acta Chem. Scand. B 1996, 50, 189-194. (d) Williams, J. M. J. Synlett 1996, 705710. (18) Feringa, B. L. Acc. Chem. Res. 2000, 33, 346-353. (19) (a) Seebach, D.; Beck, A. K.; Imwinkelzied, R.; Roggo, S.; Wonnacott, A. Helv. Chim. Acta 1987, 70, 954-974. (b) Pedroni, J.; Cramer, N. Chem. Commun. 2015, 51, 17647-17657. (20) For chiral ligand and amine synergistically controlling stereochemistry in transition metal-catalyzed allylic alkylation, see: (a) Krautwald, S.; Sarlah, D.; Schafroth, M. A.; Carreira, E. M. Science 2013, 340, 1065-1068. (b) Cruz, F. A.; Dong, V. M. J. Am. Chem. Soc. 2017, 139, 1029-1032. (21) Kolb, H. C.; VanNieuwenhze, M. S.; Sharpless, K. B. Chem. Rev. 1994, 94, 2483-2547. (22) Zhu, L.; Song, L.; Tong, R. Org. Lett. 2012, 14, 5892-5895. (23) (a) Perron, F.; Albizati, K. F. Chem. Rev. 1989, 89, 16171661. (b) Aho, J. E.; Pihko, P. M.; Rissa, T. K. Chem. Rev. 2005, 105, 4406-4440.
ACS Paragon Plus Environment
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
Table of Content
ACS Paragon Plus Environment
Page 6 of 6
