Noncovalent Interactions Involving Iodofluorobenzenes: The Interplay

Subscriber access provided by Kaohsiung Medical University

Article

Noncovalent Interactions Involving Iodofluorobenzenes: The Interplay of Halogen Bonding and Weak lp(O)•••#-Holearene Interactions Alexander S. Novikov, Daniil M. Ivanov, Zarina M. Bikbaeva, Nadezhda A. Bokach, and Vadim Yu. Kukushkin Cryst. Growth Des., Just Accepted Manuscript • DOI: 10.1021/acs.cgd.8b01457 • Publication Date (Web): 01 Nov 2018 Downloaded from http://pubs.acs.org on November 2, 2018

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 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 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.

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 55 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

Crystal Growth & Design

Noncovalent Interactions Involving Iodofluorobenzenes: The Interplay of Halogen Bonding and Weak lp(O)•••π-Holearene Interactions

Alexander S. Novikov,a Daniil M. Ivanov,a Zarina M. Bikbaeva,a Nadezhda A. Bokacha*, Vadim Yu. Kukushkina,b*

a

Institute of Chemistry, Saint Petersburg State University, Universitetskaya Nab. 7/9,

199034 Saint Petersburg, Russian Federation b

Institute of Macromolecular Compounds, Russian Academy of Sciences, Bolshoii Pr., 31, 199004

Saint Petersburg, Russian Federation

E-mail: [email protected], [email protected]

1 ACS Paragon Plus Environment

Crystal Growth & Design 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 2 of 55

Abstract Fluorinated

iodoarenes

such

as

1,4-diiodotetrafluorobenzene

(1,4-FIB)

and

1,3,5-

triiodotrifluorobenzene (1,3,5-FIB) were co-crystallized with the nitrosoguanidinate-nickel(II) species [Ni{NH=C(NRR’)NN(O)}2] (RR’ = Me2 1, RR’ = MePh 2, RR’ = (CH2)5 3) and structures of three adducts were studied by X-ray crystallography. The Hirshfeld surface analysis for the X-ray structures of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB) revealed that crystal packing is determined primarily by intermolecular contacts involving hydrogen and halogen atoms. In addition, FIBs are linked to the O atom of the nitroso-group via π-hole of the arene cores thus representing an unreported noncovalent bonding pattern for iodofluorobenzenes; it belongs to lone pair(O)–π hole interactions, lp(O)–πh. Results of DFT calculations followed by QTAIM analysis at the M06/DZPDKH level of theory revealed that estimated energies of the lp(O)–πh interactions are 1.3–2.2 kcal/mol (in experimental X-ray geometries of model supramolecular adducts) or 0.9–2.4 kcal/mol (in equilibrium optimized geometries of model supramolecular adducts). The geometry optimization procedure for model adducts does not change significantly the structural motifs of these systems indicating that lp(O)–πh contacts are not determined exclusively by crystal packing effects, but also exist in the isolated “gas phase” form. Our processing of the CCDC database and the theoretical calculations for TAXZAW01, featuring the shortest O•••arene distance, revealed five additional structures with overlooked lp(O)–πh contacts involving iodofluoroarene cores.

Keywords Fluorinated iodoarenes, lone pair–π hole interactions, noncovalent interactions, DFT, QTAIM, Hirshfeld surface analysis


Page 3 of 55 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


1. Introduction

Lone pair–π hole (lp–πh) interactions belong to the spectrum of inter- and intramolecular noncovalent contacts, which in the last five years have drawn increased attention.1-2 Despite a general agreement on the meaning of the term, there are slight differences in how various research groups define lp–πh contacts.3-5 Following ref5, in this work we define lp–πh interactions as “the stabilizing association between a lone pair of electrons and a π-hole, which can be described as the region of (more) positive electrostatic potential found on a (partially) empty π* orbital, typically located perpendicular to a molecular framework” (Figure 1). X Y Y

Z a1

X

Y

Y

X

Z

Y

b1

Z Z c1

Figure 1. Types of lp–πh interactions.

The lp–πh interactions can be carbon- or heteroatom-directed (e.g. contacts involving carbonyls, amides, and carboxyls in peptides and other biopolymers,6 nitro groups in nitroalkenes,7-9 electron-deficient main group element compounds like BX3, AlX3,9-10 a C atom in an electrondeficient arene,11 and the N atom(s) in a heterocycle11; Figure 1, a1), bond-directed (e.g. with a double bond in the electron-deficient arene ring12-13; b1), or cycle-directed (e.g. with electrondeficient arenes15 and heterocycles,14 or even involving electron-rich aromatic rings15; c1). These interactions were initially recognized in structural biology, where they determine structural features of Z-DNA.4, 11 The lp–πh contacts also stabilize biomolecular structures of other nucleic acids and proteins,6, 11, 16-17 contribute to molecular recognition,6, 11, 18 and affect enzymatic mechanisms.11, 19-20 In addition, πh interactions with lone pairs of neutral species and of anions are



Page 4 of 55

important for crystal engineering (e.g. these contacts control crystallization of nitrodiene species7, 21 and succinic or maleic anhydride derivatives,22 or control generation of elastic crystals of nonhalogenated compounds23) as well as for molecular recognition,12 and also in organocatalysis;4, 12 lp–πh contacts determine association in the gas phase14 and in solutions.24 Fluorinated electron-deficient aromatics are a logical choice for suitable πh-donors, and the association of perfluoro species with halide anions and organohalide species,25-28 O,27 N,26,

29

electron-donating arene (π–π stacking), and other centers has been reported. Although fluorinated iodoarenes (FIBs) comprise a class of one of the most commonly used building blocks for crystal engineering via halogen bond,12, 30-33 their application in most cases assumes utilization of iodine(s) σ-hole donor ability toward various nucleophiles (for recent works see Refs.34-37; Figure 2, a2), association with electrophilic centers via electron belt of iodine(s) (for recent works see Refs.38; b2), or their involvement in both types of contacts when σ-hole is bound to a nucleophilic centers, while electron belt is associated with an electrophile (for recent works see Refs.38-39; c2). No fluorinated iodobenzene has ever been experimentally recognized as a πh-donor (d2) toward lp oxygen centers and only single examples of lp(Halogen)•••πh,12, 40 and of πh-(electron donating aromatics)38, 41-42 (e2) have been reported.


Page 5 of 55

Nu

••

F

F

R

R a2

Nu

F

F R R'

R c2

E+

b2

•• E+

R'

R' F R

R' R'

R'

e2

••

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


Nu d2

Unknown bonding pattern when Nu ≠ Halogen

Figure 2. Unknown and reported noncovalent bonding patterns of FIBs. The color scheme is taken from Politzer’s work.9

In this work, we found that the iodofluorobenzenes can be co-crystallized with (nitrosoguanidinate)NiII species (Figure 3) and, in formed adducts, FIBs are involved in hydrogenand halogen bonding and also linked to the nitroso O atom via FIBs arene π-hole; the latter type of interaction represents an yet unreported noncovalent bonding pattern for such popular building blocks as iodofluorobenzenes.

2. Results and Discussion

2.1 Synthesis of FIB adducts. The complexes [Ni{NH=C(NRR’)NN(O)}2] (RR’ = Me2 1, RR’ = MePh 2, RR’ = (CH2)5 3; Figure 3) featuring nitrosoguanidinate ligands were synthesized by



Page 6 of 55

the cascade reaction between MeC(=NOH)NH2, NCNRR’, and NiCl2 in MeOH as we previously reported.43 Adducts 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB) (for FIBs see Figure 3) were obtained by slow co-crystallization of 1–3 and corresponding FIB, taken in a 1:2 molar ratio, from CHCl3 solutions at room temperature (RT). O

H NRR'

N N

N Ni

N O

N

N NRR'

H

RR' = Me2 1, MePh 2, (CH2)5 3 I F F

I F

F

F

I

F I

I

F

1,4-FIB

1,3,5-FIB

Figure 3. Graphical view of FIB-free complexes 1–3 (top) and FIBs (bottom) employed for this work. 2.2. General consideration of the XRD structures and relevant Hirshfeld surface analysis. In the three structures, all corresponding geometrical parameters of the nitrosoguanidine complexed are similar, within 3σ, with those of FIB-free 1–3.43 In the adducts, each complex molecule is surrounded by several molecules of FIB: four FIBs in 1•(1,4-FIB) and 2•2(1,3,5-FIB), six in 3•2(1,4-FIB) (Figures 4–6). The complexes and FIBs are connected to each other through several types of XBs, including bifurcated C–I•••(N–N=O) and C–I•••I–C, different types of hydrogen bonds (HBs), and also via short intermolecular C•••(heteroatom) contacts, viz. C•••O=N, C•••I–C, and C•••F–C. All these contacts (section 2.3), with special emphasis on C•••O=N interactions (section 2.3.3), are discussed in the sections that follow.


Page 7 of 55 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


Figure 4. Environment of 1 in 1•(1,4-FIB).

Figure 5. Environment of 2 in 2•2(1,3,5-FIB).

Figure 6. Environment of 3 in 3•2(1,4-FIB).



Page 8 of 55

In the crystal packing of all three adducts, layers of complexes alternating with FIBs (Figures S1–S3) and these layers are linked into 3D networks by various intermolecular contacts. The molecular Hirshfeld surface (visualization of short interatomic contacts using sums of appropriate vdW radii) represents an area where molecules come into contacts, and its analysis gives the possibility of an additional insight into the nature of intermolecular interactions in the crystal state. We carried out the Hirshfeld surface analysis for the X-ray structures of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB) to understand what kind of intermolecular contacts gives the largest contributions in crystal packing. For the visualization, we have used a mapping of the normalized contact distance (dnorm); its negative value enables identification of molecular regions of substantial importance for detection of short contacts. The Figure 7 depicts the Hirshfeld molecular surfaces for 1, 2, and 3 in X-ray structures of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB), respectively. In these Hirshfeld surfaces, the regions of shortest intermolecular contacts visualized by red circle areas. The main partial contributions of different intermolecular contacts to the molecular Hirshfeld surfaces are given in Table 1. Thus, the Hirshfeld surface analysis for the X-ray structures of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB) reveals that crystal packing is determined primarily by intermolecular contacts involving hydrogen atoms (F–H, N–H, O–H, H–H, I–H, and C–H). Intermolecular contacts C–O, I–O and I–N give small contributions to the formation of Hirshfeld molecular surfaces for 1, 2, and 3 in the X-ray structures of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB) (Table 1). Insofar as the Hirshfeld surface analysis does not answer the question of energies of all these contacts, the density functional theory (DFT) calculations (Section 2.4) should be further performed.


Page 9 of 55 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


Figure 7. Hirshfeld molecular surfaces for 1 (top), 2 (center), and 3 (bottom) in the X-ray structures of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB), respectively.

Table 1. Results of the Hirshfeld surface analysis for the X-ray structures of 1•(1,4-FIB), 2•2(1,3,5FIB), and 3•2(1,4-FIB). X-ray structure 1•(1,4-FIB) 2•2(1,3,5-FIB) 3•2(1,4-FIB)

Relative contributions of different intermolecular contacts to the molecular Hirshfeld surface* F–H 22.5%, N–H 19.4%, O–H 14.2%, H–H 10.6%, I–H 9.0%, C–H 5.8%, Ni–H 4.3%, N–N 3.6%, I– O 2.0%, I–N 1.8%, O–C 1.8%, N–C 1.7%, F–O 1.4% H–H 19.2%, F–H 18.7%, I–H 13.8%, C–H 11.6%, N–H 10.6%, O–H 9.2%, I–C 4.2%, I–O 1.9%, O– C 1.8%, I–N 1.7%, F–N 1.7%, N–C 1.5%, F–C 1.3%, Ni–H 1.2%, Ni–F 1.1% H–H 25.8%, F–H 22.7%, N–H 14.2%, I–H 9.5%, O–H 5.1%, C–H 5.0%, Ni–H 4.5%, I–N 4.2%, I–O 3.7%, O–C 2.8%

* The percentages reflect the size of the molecular Hirshfeld surface section, which is formed due to the corresponding interatomic contacts. The contributions of all other intermolecular contacts do not exceed 1%.

2.3. Observed weak interactions. We consider structure-determining weak interactions in descending order of their contribution into crystal structure of the studied adducts. Accordingly, more conventional hydrogen- (section 2.3.1) and halogen (section 2.3.2) bondings are given ahead



Page 10 of 55

of the unusual C•••O=N contacts of the lp(O)–πh type (section 2.3.3); these interactions have never been recognized in the past for any of iodofluorobenzenes despite a very broad usage of these species in crystal engineering involving XB. 2.3.1. Hydrogen bonding. In the crystal structures of all adducts, we identified the following HBs: N–H•••F HB in 1•(1,4-FIB) and 3•2(1,4-FIB), C–H•••F in 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB), C–H•••I in 1•(1,4-FIB), C–H•••O= in 1•(1,4-FIB) and 2•2(1,3,5-FIB), and C–H•••N in 2•2(1,3,5-FIB) (Table 2). As is follows from Table 2, the strongest HB was found in 3•2(1,4-FIB), where one fluorine atom F2S simultaneously forms two HBs with H2B–C2 and H3–N3 moieties that results in formation of 7-membered cycle. Table 2. Parameters of HB in the studied adducts. Contact A–H•••B H•••B, Å R¶ A•••B, Å ∠(A–H•••B),° N3–H3•••F2S 2.589(2) 0.97 3.424(4) 163.8(2) C3–H3C•••O1 2.566(2) 0.94 3.445(5) 152.4(2) C2–H2B•••F1S 2.509(2) 0.94 3.393(5) 153.1(3) C2–H2C•••I1S 3.1066(4) 0.98 4.066(4) 178.2(3) 2•2(1,3,5-FIB) C2–H2B•••O1 2.465(2) 0.91 3.389(3) 161.9(2) C4–H4•••N2 2.598(2) 0.94 3.441(3) 151.0(2) C5–H5•••F2S 2.663(2) 1.00 3.210(3) 118.3(2) 3•2(1,4-FIB) N3–H3•••F2S 2.4021(2) 0.90 3.248(3) 168.0(2) C2–H2B•••F2S 2.443(2) 0.91 3.405(3) 171.7(2) ¶ R is interatomic distance to vdW sum ratio, the sum of Bondi vdW radii44 RvdW(H) + RvdW(O) = 2.72, RvdW(H) + RvdW(N) = 2.75, RvdW(H) + RvdW(F) = 2.67, and RvdW(H) + RvdW(I) = 3.18 Å. Adduct 1•(1,4-FIB)

2.3.2 Bifurcated C–I•••(N–N=O) halogen bonding. The most significant, structuredetermining type of short contacts, observed in adducts of (nitrosoguanidinate)NiII species with XB donors (see our recent publication40 and also this work), is bifurcated C–I•••(N–N=O) XBs (Figure 8). Each adduct studied in this work form one type of bifurcated C–I•••(N–N=O) XB; parameters of the C–I•••(N–N=O) moiety are summarized in Table 3. The distances C–I•••O and C–I•••N (3.035(2)–3.090(2) and 3.298(2)–3.402(2) Å, correspondingly) are shorter than the appropriate sums of Bondi vdW radii (RvdW(I) + RvdW(O) = 3.50 and RvdW(I) + RvdW(N) = 3.53 Å).44 The corresponding angles ∠(I–I•••O) and ∠(I–I•••N) vary in the ranges 156.28(11)–164.98(8) and


Page 11 of 55 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


153.14(11)–158.32(8)° thus satisfying the IUPAC criteria for XB.45 At the same time, in the structure of 3•2(1,4-FIB) another similar contact, namely between the I2S atom and the nitrosoguanidinate ligand, was also detected. In 3•2(1,4-FIB), the parameters of C4S–I2S•••N2 contact (I2S•••N2 3.148(2) Å and ∠(C4S–I2S•••N2) 168.53(8)°) match the known criteria for XB, while the parameters of C4S–I2S•••O1 contact (I2S•••O1 3.426(2) Å and ∠(C4S–I2S•••N2) 137.81(7)°) deviate by the angle criterion.45 Therefore for 3•2(1,4-FIB) only C4S–I2S•••N2 contact can be unequivocally attributed to XB, whereas the bifurcated C–I•••(N–N=O) XB in this case is not formed probably because of steric reasons. X

H NRR'

O

N N

X = F, I

N Ni

N O

N

F

X

X I

X

F

X (CH2)5N

N

O

H

NRR'

H

N N

Ni N O

1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB)

N

I

I F

F

N

N

N(CH2)5

H

3•2(1,4-FIB)

Figure 8. C–I•••(N–N=O) bifurcated XBs in 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB) (left) and C–I•••N XB in 3•2(1,4-FIB) (right).

Results of DFT calculations and QTAIM analysis (section 2.4) reveal that the C–I•••(N– N=O) contacts are stronger than C–I•••(N–N=O) contacts both in the experimental X-ray geometries (by 1.3–1.6, 0.8–0.9, and 1.5–1.6 kcal/mol in the cases of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4FIB), respectively) and equilibrium optimized geometries of model supramolecular adducts (by 0.6– 0.8, 0.0–0.3, and 0.5–0.6 kcal/mol in the cases of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB), respectively).



Page 12 of 55

Table 3. Parameters of the C–I•••(N–N=O) XB in the adducts (X = O or N). Adduct 1•(1,4-FIB)

Contact I•••X, Å C2S–I1S•••O1 3.035(2) C2S–I1S•••N2 3.327(3) 2•2(1,3,5-FIB) C5S–I3S•••O1 3.090(2) C5S–I3S•••N2 3.298(2) 3•2(1,4-FIB) C1S–I1S•••O1 3.052(2) C1S–I1S•••N2 3.402(2) ¶ R is interatomic distance to vdW sum ratio, the sum of Bondi RvdW(N) = 3.53 Å.

R¶ 0.87 0.94 0.88 0.93 0.87 0.96 vdW radii44 RvdW(I)

∠(C–I•••X),° 156.28(11) 153.14(11) 164.98(8) 153.38(8) 162.41(7) 158.32(8) + RvdW(O) = 3.50 and RvdW(I) +

The observed bifurcated XB between any of the I centers and O or N centers was early reported only by us40 for relevant adducts of the (nitrosoguanidinate)NiII complexes with XB donors. The CCDC data search revealed two more structures (TIPPAL, TIPPUF)46 with the {terminal I}•••(N{spacer}O) moieties (Figure 9; parameters of XBs are I•••N 3.459(3) (TIPPAL) and 3.503(3) Å (TIPPUF), I•••O 3.457(3) (TIPPAL) and 3.483(2) Å (TIPPUF), ∠(C–I•••N) 156.56(13) (TIPPAL) and 157.53(8)° (TIPPUF), ∠(C–I•••O) 162.56(10) (TIPPAL) and 163.72(8)° (TIPPUF); for the sums of appropriate Bondi vdW radii see footnote to Table 3), but this bifurcated XB contacts were overlooked in the article.46 MeO MeO

N N

MeO

I

N

I

N R

O Me

R

Figure 9. C–I•••(N–C–O) XBs in the structures of TIPPAL (R = Naphth) and TIPPUF (R = 2,3,4-(MeO)3C6H2).

2.3.3. The C•••O=N contacts. Most interesting types of weak interactions between 1–3 and FIBs are C•••O=N contacts of the π-system of an electron deficient arene and the O atom of the nitrosoguanidinate ligands (Figure 10). Parameters of the C•••O=N contacts are summarized in


Page 13 of 55 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 4. In all cases, the C•••O=N separations are shorter than the sum of Bondi vdW radii and the ∠(C•••O–N) angles vary in the wide range 86.30(13)–164.4(2)°. The shortest C•••O distance (2.903(3) Å; Bondi vdW radii44 is RvdW(C) + RvdW(O) = 3.22 Å) with the ∠(C•••O–N) angle of 159.06(16)° was found in 3•2(1,4-FIB). This short contact is supported/accompanied with the N– H•••F2S and C–H•••F2S HBs (Figure 6).

X

X

X

X F

H NRR'

O

N N

X

N Ni

N O

N

N

NRR'

H

X = F, I

Figure 10. The C•••O=N contact in adducts 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB).

The longest contacts (3.132(3) and 3.186(3) Å, that are still less than Bondi vdW radii sum, 3.22 Å) were identified for the adduct with the least fluorinated FIB, i.e. 2•2(1,3,5-FIB), and this weak interaction is characterized by the smallest ∠(C•••O–N) angles (86.30(13) and 111.50(14)°, correspondingly) among the three adducts.

Table 4. Parameters of C•••O=N contacts in the adducts. Contact C•••O, Å R¶ ∠(C•••O=N),° C3S•••O1–N1 3.067(4) 0.95 164.4(2) C4S•••O1–N1 3.132(3) 0.97 86.30(13) C3S•••O1–N1 3.186(3) 0.99 111.50(14) 3•2(1,4-FIB) C3S•••O1–N1 2.903(3) 0.90 159.06(16) ¶ R is interatomic distance to vdW sum ratio, the sum of Bondi vdW radii44 is RvdW(C) + RvdW(O) = 3.22 Å. Adduct 1•(1,4-FIB) 2•2(1,3,5-FIB)



Page 14 of 55

The observed C•••O=N contacts belong to lp–πh interactions involving fluorinated arenes acting as π-hole donors. Although FIBs were broadly applied for supramolecular assembly via XB,16, 47-49 in only few instances these species capable of forming lp–πh interactions. Our processing of CCDC database revealed 5 structures where FIBs (but not all fluorinated arene systems) form lp– πh contacts with various O-nucleophilic centers (Table 5). In these structures, water (LOFDEQ), substituted phenol (IWONAL), 1,3-oxazole (COGKAM), amide (IRUHOT) and 1,3-diketone (TAXZAW01) act as O donors. Important that in all five reports,16, 47, 50-52 the C•••O contacts were overlooked.

Table 5. Parameters of C•••O contacts in the reported adducts. CCDC Code

Fragment of Adduct, C•••O, Å R* Refs. O•••FIB 47 TAXZAW01 {С=O}•(1,4-FIB) 3.187(3) 0.99 50 COGKAM {Osp3}•(1,4-FIB) 3.201(3) 0.99 51 IRUHOT {С=O}•(C6F5I) 3.123(11) 0.97 52 IWONAL {HOsp3}•(1,2-FIB) 3.191(8) 0.99 16 LOFDEQ {H2O}•(1,3,5-FIB) 3.014(4) 0.94 * 44 R is interatomic distance to vdW sum ratio, the sum of Bondi vdW radii is RvdW(C) + RvdW(O) = 3.22 Å.

In the context of lp(O)–πh interactions, it is noteworthy that although these interactions with FIBs were identified only in this work, limited cases of lp(O)–πh interactions were previously reported for some other fluorinated aromatics. Examples of lp(O)–πh interactions involving O centers and fluorinated arenes include: C•••O contacts for functionalized alcohols (Figure 11, a11),53 lp(O)–πh interactions between alcohols and perflourosubstituted organics (a9; R = Me),54 intramolecular contact between the O center of ether-fluorinated arene ring (b9),25 and furan oxygen–fluorinated arene ring interaction (c9).55 A related antiparallel C–F•••C=O stacking interaction, which is important in the stabilization of the supramolecular assemblies, has been found in Ref.56 for the mercury(II) complex [Hg(L)2]n [L = N1-(3-hydroxypropyl)-5-fluorouracylate]. In


Page 15 of 55 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


Ref.,57 the lp(O)–πh contact between the fluorine and the pyrimidine ring was detected for the 5fluoro-1-hexyluracil.

R R'2N

H

O

F

Me

r

e ac

O

sp

F

F

O F

F F

S

F

F

S

F

F

F

F b11

a11

F

F c11

Figure 11. Examples of lp–πh interactions involving fluorinated arenes and O centers.

The studies of association of oxygen centers with πh-donor electron-deficient arenes are motivated in part by the need of understanding of the unusual phenomenon of water solubility in solutions of fluorinated aromatics.58 Two more issues are noteworthy. First, although in the vast majority of cases Rowland radii59 are used for the recognition of noncovalent interactions,60-64 in this work we use Bondi radii44 (the shortest) to provide confident recognition of lp(O)–πh contacts. If for the identification of the lp(O)–πh interactions the same approach as the one recommended by IUPAC for identification of XBs is applied,65 the distance criterion alone can not be taken as exhaustive. IUPAC recommends the usage of “the bond critical point criterium” in addition to “the distance criterion”. For the studied systems both the bond critical point (section 2.4.1) and distance criteria (this section) are fully obeyed. Furthermore, in addition to single point DFT calculations based on the experimental X-ray geometries, we performed geometry optimization (section 2.4.2), which does not change significantly the structural motifs of these systems indicating that lp(O)–πh contacts are not determined exclusively by crystal packing effects, but also exist in the isolated “gas phase” form. It



Page 16 of 55

means that the lp(O)–πh interactions are the real and they cannot be categorized as crystal packing effects. Eventually, we found similar lp(O)–πh interactions at some other XRD structures taken form CSD (section 2.5) and this statistical approach collaterally confirms accuracy of our recognition of the lp(O)–πh interactions. Second, there is some ambiguity in attribution of the bonding that we observed to lp–πh or to tetrel bonding. Although tetrel bonding is not yet defined by IUPAC, we assume that it should have certain similarities with halogen bonding insofar as it also provided by interaction with low-lying σ∗-orbitals; both interactions belong to the so-called σ-hole interactions. As can be inferred from our consideration of XRD geometrical parameters, in particular 2•2(1,3,5-FIB), the O nucleophilic center is linked to two C atoms of the π-system. Hence, the term “lp–πh bonding” is more general for description of the studied systems than the “tetrel bonding” as the former can be applied for both atom- and bond-centered noncovalent interactions. 2.3.4. Other observed short contacts. Although the corresponding distances are slightly longer than the vdW sums, our theoretical calculations performed for XRD determined atomic coordinates (section 2.4.1) also confirmed the presence of the lp(I)•••πh(C) and lp(F)•••πh(N) interactions and the C–I•••C XBs in 2•2(1,3,5-FIB). The FIBs also form contacts with each other (Figure 12, Table 6). In 3•2(1,4-FIB), 1,4-FIB form C•••F–C contacts and C–F•••F–C type I halogen•••halogen contacts (a12). In adducts 2•2(1,3,5-FIB), 1,3,5-FIBs are connected with each other via C–I•••I–C XBs and C•••I–C interactions whose existence was additionally confirmed by theoretical calculations (b12).

Table 6. Parameters of short contacts formed between FIB molecules. Adduct 2•2(1,3,5-FIB) 3•2(1,4-FIB)

Contact C1S–I1S•••I2S–C3S C1S•••I3S–C1S C4S•••F1S–C2S C6S–F4S•••F4S–C6S

A•••B, Å 3.7209(4) 3.701(2) 3.076(3) 2.858(3)

R¶ 0.94 1.01 0.97 0.97

∠(A•••B–X),° 106.74(7) 88.57(8) 109.07(14) 97.56(14)


∠(X–A•••B)° 172.39(7) 97.56(14)

Type of contact XB lp(I)•••πh(C) lp(F)•••πh(C) type I halogen•••halogen

Page 17 of 55 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


¶

R is interatomic distance to vdW sum ratio, the sum of Bondi vdW radii44 is RvdW(F) + RvdW(F) = 2.94, RvdW(C) + RvdW(F) = 3.17, RvdW(I) + RvdW(I) = 3.96, RvdW(C) + RvdW(I) = 3.68,Å.

a12

b12 Figure 12. FIBs contacts in the studied adducts. 2.4. Noncovalent interactions in the adducts: a theoretical approach. 2.4.1. Theoretical study of experimental X-ray geometries of model supramolecular clusters 1•(1,4-FIB)4, 2•(1,3,5FIB)4, and 3•(1,4-FIB)6. Inspection of the crystallographic data suggests the presence of various noncovalent interactions responsible for the formation of a supramolecular structures of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB). Considering this, in addition to structural analysis, detailed computational study is desirable. In order to confirm or disprove the hypothesis on the existence of



Page 18 of 55

these supramolecular contacts and quantify their energies from a theoretical viewpoint, we carried out DFT calculations and performed topological analysis of the electron density distribution within the framework of Bader’s theory (QTAIM method)66 for model supramolecular clusters 1•(1,4FIB)4, 2•(1,3,5-FIB)4, and 3•(1,4-FIB)6 (Supporting Information, Table S2). This approach has already been successfully used by us upon studies of different noncovalent interactions (e.g., hydrogen, halogen, and chalcogen bonding, metallophilic interactions, and stacking) in various organic, organometallic and coordination compounds (for recent works see Refs.67-70 and references therein). Results are summarized in Table 7, the contour line diagrams of the Laplacian distribution ∇2ρ(r), bond paths, and selected zero-flux surfaces for 1•(1,4-FIB)4, 2•(1,3,5-FIB)4, and 3•(1,4FIB)6 are shown in Figure 13 and Figures S4–S5. To visualize studied noncovalent interactions, reduced density gradient (RDG) analysis71 was carried out, and RDG isosurfaces for 1•(1,4-FIB)4, 2•(1,3,5-FIB)4, and 3•(1,4-FIB)6 were plotted (Figure 13 and Figures S4–S5). Table 7. Values of the density of all electrons – ρ(r), Laplacian of electron density – ∇2ρ(r), energy density – Hb, potential energy density – V(r), and Lagrangian kinetic energy – G(r) (a.u.) at the bond critical points (3, –1), corresponding to different noncovalent interactions in experimental Xray geometries of model supramolecular clusters 1•(1,4-FIB)4, 2•(1,3,5-FIB)4, and 3•(1,4-FIB)6, bond lengths – l (Å), as well as energies for these contacts Eint (kcal/mol), defined by two approaches,* and appropriate Wiberg bond indices (WI). Einta

Eintb

l

WI

3.5 1.9 1.3 0.9 1.3

3.5 2.2 1.6 1.1 1.3

3.035 3.327 3.067 2.589 3.107

0.03 0.01 0.00 0.00 0.01

2.2 3.1

2.2 3.0

0.005

1.3

1.3

0.005 0.005 0.003

1.3 0.9 0.6

1.3 1.3 0.8

3.298 3.090 3.132 (C68•••O36) 3.186 (C64•••O36) 3.349 3.039 3.701 3.728

0.01 0.03 0.00 (C68•••O36) 0.00 (C64•••O36) 0.00 0.00 0.00 0.00

ρ(r)

∇2ρ(r)

Hb

I56•••O14 I56•••N18 C4•••O14 H32•••F3 H43•••I1

0.016 0.010 0.006 0.005 0.007

0.055 0.035 0.029 0.020 0.024

0.001 0.001 0.002 0.001 0.001

N40•••I72 O36•••I72

0.011 0.014

0.037 0.048

0.001 0.001

1•(1,4-FIB)4 –0.011 0.013 –0.006 0.008 –0.004 0.006 –0.003 0.004 –0.004 0.005 2•(1,3,5-FIB)4 –0.007 0.008 –0.010 0.011

C64=C68•••O36

0.007

0.026

0.001

–0.004

Ni13•••F61 N37•••F61 C65•••I72 I58•••C34

0.006 0.007 0.005

0.026 0.023 0.018

BCP not found 0.001 –0.004 0.001 –0.003 0.001 –0.002

Contact

V(r)

G(r)


Page 19 of 55 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


3•(1,4-FIB)6 I94•••O14 0.015 0.052 0.001 –0.010 0.012 3.1 O14•••I106 0.008 0.030 0.001 –0.005 0.006 1.6 N16•••I94 0.008 0.030 0.001 –0.005 0.006 1.6 N16•••I106 0.014 0.045 0.001 –0.009 0.010 2.8 C6•••O14 0.008 0.039 0.002 –0.006 0.008 1.9 C109•••F3 0.007 0.027 0.001 –0.004 0.005 1.3 H18•••F65 0.007 0.030 0.001 –0.005 0.006 1.6 H23•••F65 0.007 0.031 0.002 –0.005 0.006 1.6 a Eint = –V(r)/2 72 b Eint = 0.429G(r) 73 * Tsirelson et al.74 also proposed alternative correlations developed exclusively for iodine atoms, viz. Eint = 0.68(−V(r)) or Eint = 0.67G(r).

3.2 1.6 1.6 2.7 2.2 1.3 1.6 1.6

3.052 3.426 3.402 3.148 2.903 3.076 2.402 2.443

0.02 0.00 0.01 0.02 0.01 0.00 0.00 0.00

noncovalent interactions involving

Figure 13. Contour line diagrams of the Laplacian distribution ∇2ρ(r), bond paths and selected zero-flux surfaces (left) and RDG isosurface (right) referring to noncovalent interactions C•••O=N (top) and C–I•••(N–N=O) (bottom) in 1•(1,4-FIB)4. Bond critical points (3, –1) are shown in blue, nuclear critical points (3, –3) – in pale brown, ring critical points (3, +1) – in orange, cage critical points (3, +3) – in light green, RDG isosurface values are given in a.u.



Page 20 of 55

The QTAIM analysis of the experimental X-ray geometries of model supramolecular clusters 1•(1,4-FIB)4, 2•(1,3,5-FIB)4, and 3•(1,4-FIB)6 demonstrates the presence of appropriate bond critical points (3, –1) (BCPs) for all noncovalent interactions listed in Table 7. The low magnitude of the electron density (0.005–0.016 a.u.), positive values of the Laplacian (0.018–0.055 a.u.), and very close to zero positive energy density (0.001–0.002 a.u.) in these BCPs are typical for noncovalent interactions. We have defined energies for these contacts according to the correlations proposed by Espinosa et al.72 and Vener et al.,73 and one can state that strength of these contacts vary from 0.6 to 3.5 kcal/mol. The balance between the Lagrangian kinetic energy G(r) and potential energy density V(r) at the BCPs reveals the nature of these interactions, if the ratio –G(r)/V(r) > 1 is satisfied, than the nature of appropriate interaction is purely noncovalent, in case the –G(r)/V(r) < 1 some covalent component takes place.75 Based on this criterion one can state that a covalent contribution is absent in all supramolecular contacts listed in Table 7. The negligible values of the Wiberg bond indices for these supramolecular contacts (0.00–0.03) additionally confirm their electrostatic nature. 2.4.2. Theoretical study of equilibrium optimized geometries of the model supramolecular adducts. In order to clarify, whether various noncovalent interactions—responsible for the formation of the supramolecular structures—are explained by the crystal packing effects or are specific properties of these associates, we have also carried out the geometry optimization procedure in the gas phase for model supramolecular clusters 1•(1,4-FIB)4, 2•(1,3,5-FIB)4, and 3•(1,4-FIB)6 and used the resulting equilibrium geometries for topological analysis of the electron density distribution (Table 8). If the crystal packing effects are significant, the structures should change appreciably on going from the solid state to the gas phase, otherwise the geometries of model systems, as expected, are preserved in the isolated form. Also, it is well known that X-ray diffraction experiments cannot indicate the precise location of H atoms, and this approach allows the refinement of the positions of Hs atoms from quantum chemistry viewpoint.


Page 21 of 55 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


The geometry optimization procedure for the model clusters does not change significantly the structural motifs of these systems (Tables 8 and S2). In 1•(1,4-FIB)4, the I56•••O14 contact is elongated on going from the solid state to the gas phase (by 0.071 Å), whereas I56•••N18, C4•••O14, H32•••F3, and H43•••I1 contacts are shortened (by 0.440 Å, 0.189 Å, 0.256 Å, and 0.046 Å, respectively). The estimated strengths of I56•••O14, I56•••N18, C4•••O14, H32•••F3, and H43•••I1 noncovalent interactions in equilibrium optimized geometry of 1•(1,4-FIB)4, vary from 1.3 to 3.0 kcal/mol. In 2•(1,3,5-FIB)4, the N40•••I72, O36•••I72, and C68•••O36 contacts are elongated on going from the solid state to the gas phase (by 0.061, 0.165, and 0.016 Å, respectively), whereas Ni13•••F61 and N37•••F61 contacts are shortened (by 0.391 and 0.172 Å, respectively). It is noteworthy that QTAIM analysis of equilibrium optimized geometry of 2•(1,3,5-FIB)4 reveal the presence of BCPs for Ni13•••F61, C67•••I72, and I58•••C24 contacts, and absence of BCPs for C65•••I72 and I58•••C34 contacts. The estimated strengths of N40•••I72, O36•••I72, C68•••O36, Ni13•••F61, N37•••F61, C67•••I72, and I58•••C24 noncovalent interactions in equilibrium optimized geometry of 2•(1,3,5-FIB)4 vary from 0.9 to 2.2 kcal/mol. In 3•(1,4-FIB)6, the I94•••O14, O14•••I106, H18•••F65, and H23•••F65 contacts are elongated on going from the solid state to the gas phase (by 0.269, 0.184, 0.775, and 1.167 Å, respectively), whereas N16•••I94, N16•••I106, and C6•••O14 contacts are shortened (by 0.209, 0.061, and 0.006 Å, respectively). The QTAIM analysis of equilibrium optimized geometry of 3•(1,4-FIB)6 reveal the presence of BCP for C110•••F3 contact instead of C109•••F3 contact and does not locate the BCPs for O14•••I106, H18•••F65, and H23•••F65 contacts. The estimated strengths of I94•••O14, N16•••I94, N16•••I106, N16•••I106, C6•••O14, and C110•••F3 noncovalent interactions in equilibrium optimized geometry of 3•(1,4FIB)6 vary from 1.6 to 3.5 kcal/mol. Thus, all discussed noncovalent interactions with only few exceptions (viz. C65•••I72 and I58•••C34 contacts in 2•(1,3,5-FIB)4 and O14•••I106, H18•••F65, and H23•••F65 contacts in 3•(1,4-FIB)6) are not determined exclusively by crystal packing effects, but also exist in the isolated “gas phase” form.




Page 22 of 55

Page 23 of 55 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 8. Values of the density of all electrons – ρ(r), Laplacian of electron density – ∇2ρ(r), energy density – Hb, potential energy density – V(r), and Lagrangian kinetic energy – G(r) (a.u.) at the bond critical points (3, –1), corresponding to different noncovalent interactions in equilibrium optimized geometries of model supramolecular clusters 1•(1,4-FIB)4, 2•(1,3,5-FIB)4, and 3•(1,4FIB)6, bond lengths – l (Å), as well as energies for these contacts Eint (kcal/mol), defined by two approaches,* and appropriate Wiberg bond indices (WI). Contact

ρ(r)

∇2ρ(r)

I56•••O14 I56•••N18 C4•••O14 H32•••F3 H43•••I1

0.014 0.011 0.009 0.009 0.008

0.047 0.038 0.043 0.034 0.025

N40•••I72 O36•••I72 C68•••O36 Ni13•••F61 N37•••F61 C67•••I72 I58•••C24

0.010 0.010 0.006 0.009 0.009 0.008 0.007

0.035 0.035 0.023 0.039 0.040 0.027 0.023

Hb

V(r)

1•(1,4-FIB)4 0.001 –0.009 0.001 –0.007 0.002 –0.006 0.001 –0.006 0.001 –0.004 2•(1,3,5-FIB)4 0.001 –0.006 0.001 –0.006 0.001 –0.003 0.001 –0.007 0.002 –0.006 0.002 –0.004 0.001 –0.004 3•(1,4-FIB)6 0.001 –0.006 BCP not found 0.001 –0.008 0.001 –0.011 0.002 –0.006 0.002 –0.005 BCP not found BCP not found

I94•••O14 0.009 0.035 O14•••I106 N16•••I94 0.012 0.043 N16•••I106 0.015 0.050 C6•••O14 0.008 0.040 C110•••F3 0.008 0.034 H18•••F65 H23•••F65 a Eint = –V(r)/2 72 b Eint = 0.429G(r) 73 * Tsirelson et al.74 also proposed alternative correlations developed iodine atoms, viz. Eint = 0.68(−V(r)) or Eint = 0.67G(r).

G(r)

Einta

Eintb

l

WI

0.011 0.008 0.009 0.007 0.005

2.8 2.2 1.9 1.9 1.3

3.0 2.2 2.4 1.9 1.3

3.106 3.283 2.878 2.333 3.061

0.02 0.01 0.01 0.01 0.01

0.007 0.008 0.005 0.008 0.008 0.005 0.005

1.9 1.9 0.9 2.2 1.9 1.3 1.3

1.9 2.2 1.3 2.2 2.2 1.3 1.3

3.359 3.255 3.148 2.958 2.867 3.607 3.565

0.01 0.02 0.00 0.01 0.00 0.01 0.00

0.007

1.9

1.9

0.009 0.012 0.008 0.007

2.5 3.5 1.9 1.6

2.4 3.2 2.2 1.9

3.321 3.610 3.193 3.087 2.897 2.976 3.177 3.610

0.01 0.00 0.02 0.03 0.01 0.00 0.00 0.00

exclusively for noncovalent interactions involving

2.5. Recognition of lp(O)–πh contacts in the structure of TAXZAW01. To obtain more arguments favoring the existence of lp(O)–πh contacts involving iodofluoroarene cores, apart from CCDC search for such contacts (Table 5), we chose the structure TAXZAW01 with the shortest Carene•••O distance and for this structure we carried out the same DFT calculations together with QTAIM analysis. For the calculations we addressed two types of model supramolecular adducts obtained from the TAXZAW01 X-ray structure, where FIB forms C•••O lp–πh contact with the Onucleophilic center (Figure 14; Tables 9 and S2). Two types of model supramolecular clusters



Page 24 of 55

differ by the position of the H atom and both adducts were found in the experimental X-ray structure (Figure 15).

Figure 14. Contour line diagram of the Laplacian distribution ∇2ρ(r), bond paths and selected zeroflux surfaces (left) and RDG isosurface (right) referring to C•••O lp–πh noncovalent interactions in equilibrium optimized geometry of model supramolecular adducts TAXZAW01_1. Bond critical points (3, –1) are shown in blue, nuclear critical points (3, –3) – in pale brown, ring critical points (3, +1) – in orange, RDG isosurface values are given in a.u.


Page 25 of 55 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


F

F

F

I

I

I F

I F

F O

F

H

O

O

N

F

N

H

O

N

N

Figure 15. Two types of model supramolecular adducts for TAXZAW01 structure from CCDC database.

Table 9. Values of the density of all electrons – ρ(r), Laplacian of electron density – ∇2ρ(r), energy density – Hb, potential energy density – V(r), and Lagrangian kinetic energy – G(r) (a.u.) at the bond critical points (3, –1), corresponding to C•••O lp–πh noncovalent interactions in experimental X-ray and equilibrium optimized geometries of model supramolecular adducts TAXZAW01_1 and TAXZAW01_2, bond lengths – l (Å), as well as energies for these contacts Eint (kcal/mol), defined by two approaches. Structure Experimental X-ray geometry of TAXZAW01_1 Equilibrium optimized geometry of TAXZAW01_1 Experimental X-ray geometry of TAXZAW01_2 Equilibrium optimized geometry of TAXZAW01_2 a Eint = –V(r)/2 72 b Eint = 0.429G(r) 73

ρ(r)

∇2ρ(r)

Hb

V(r)

G(r)

Einta

Eintb

l

0.006

0.021

0.001

–0.003

0.004

0.9

1.1

3.187

0.008

0.031

0.002

–0.004

0.006

1.3

1.6

3.053

0.006

0.021

0.001

–0.003

0.004

0.9

1.1

3.187

BCP not found

3.272

In the case of TAXZAW01_1, the geometry optimization procedure leads to the shortening of C•••O lp–πh contact (by 0.134 Å), whereas in case of TAXZAW01_2 the C•••O lp–πh contact is



Page 26 of 55

elongated (by 0.085 Å). For TAXZAW01_1, the QTAIM analysis reveals the presence of BCPs for C•••O lp–πh contacts both in the experimental X-ray and equilibrium optimized geometries of model supramolecular adduct, whereas for TAXZAW01_2 appropriate BCP was found only in the experimental X-ray geometry of the model supramolecular adduct. The values of electron density, Laplacian of electron density, and energy density in BCPs for these C•••O lp–πh contacts are typical for noncovalent interactions. The estimated strength of C•••O lp–πh contacts in model supramolecular adducts TAXZAW01_1 and TAXZAW01_2 vary from 0.9 to 1.6 kcal/mol.

3. Conclusions

FIBs are useful building blocks in the subfield of crystal engineering, which utilizes halogen bonding.12,

30-31

The popularity of these species (particularly 1,4-diiodotetrafluorobenzene) is

reflected in a rapidly growing amount of works that employ FIBs as bi- or polyfunctional halogen bond donors for supramolecular assembly. The π-hole donor properties of FIBs are substantially less explored, but a few examples of their π-hole donor ability still have been found or predicted by theoretical calculations. Thus, 1,2-diiodotetrafluorobenzene in the adduct (acridine)•1,2-FIB forms the double antiparallel C•••F contact (Figure 16, a16).76 Wang et al.77 demonstrated by solution NMR method a competition of lp–π hole and lp–σ hole halogen bonding interactions between C6F5X (X = Cl, Br, I) and solvent molecules (CD3OD, dmso-d6, acetone-d6, MeCN-d3) (Figure 16, b16). Theoretical calculations78 indicate a small weakening effect of coexistence of halogen bonding and lp–πh interactions in 1,4-FIB.


Page 27 of 55

I

I

F

Y

F F

F

F

F

F F

F

F

F F

I

I

Y

F

Y − solvent

I a16

b16

Figure 16. Examples of lp–πh interactions involving FIBs (a16) in the solid state, in the adduct (C6H4)2CHN•1,2FIB; (b16) C6F5I in various solvents acting as lp-donors.

In this work, we demonstrated that fluorinated iodobenzenes 1,4-FIB and 1,3,5-FIB (Figure 3) co-crystallize with nickel(II) nitrosoguanidinates 1–3 giving supramolecular structures held by several types of contacts, including rather conventional HB and XB, and the unusual lp(O)– πh weak interactions. The observation of O•••C lp–πh contacts involving arene rings of FIB and oxygen lone pairs is the first recognition of this noncovalent bonding pattern.

F

F

Nu

••

R

R

••

Nu

a17

E+

••

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


Nu

b17

Figure 17. Bifunctional interactions including lp(O)–πh contacts of FIBs. The color scheme is taken from Politzer’s work.9



Page 28 of 55

Our inspection of the literature on the topic along with processing of relevant data obtained from the CCDC database indicate that lp(O)–πh interactions of FIBs are not unusual but overlooked phenomenon. We believe that the role of FIBs as building blocks in supramolecular chemistry and crystal engineering can be diversified by the use of their π-hole donor properties. Choice of proper partners bearing several acceptor centers such as, for example, heteroatoms with lone pairs, electron donating π-systems and aromatic rings etc. (Figure 17), for co-crystallization with FIBs should stimulate appearance πh-involving interactions accompanied with XB.

4. Experimental Syntheses of the adducts. For preparation of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB), any one of 1–3 (0.035 mmol) was added to a solution of appropriate FIB (0.07 mmol) in CHCl3 (10 mL) placed in a 20-mL round-bottomed flask. The reaction mixture was stirred under ultrasonic treatment at 20–25 °C until the complete homogenization and then left to stand at room temperature for slow evaporation. Dark red crystals of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB), suitable for X-ray diffraction studies, were released after 7–9 d. X-ray structure determinations. Suitable single crystals of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB) were selected, fixed on a micro mount, placed on an Agilent Technologies Excalibur Eos diffractometer and measured at a temperature of 100(2) K using monochromated Mo Kα (λ = 0.7107) radiation. Using Olex2,79 the structure was solved with the ShelXT80 structure solution program using Intrinsic Phasing and refined with the ShelXL80 refinement package using Least Squares minimization. Parameters used for the CSD search. For the search we used off-line CCDC database (version 1.21; February 2018). One fragment was a hexahalobenzene ring with any halogen atom at each position. Another fragment was an O atom without specification of its charge, number of


Page 29 of 55 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


neighboring atoms, and the nature of bonds with these neighbors. Next, the distance between any C atom of the benzene system and the O atom was set in the range between 2.00 and 3.22 Å, the latter being the sum of the C and O Bondi vdW radii. In the search, we considered both intra- and intermolecular interactions; no restrictions for R-values and disordered structures were set. As a result, we found 12 structures (TAXZAW01, COGKAM, EMENAL, FIYYAN, FOSZOE, IRUHOT, IWONAL, LOFDEQ, ODUSAI, PIXVUN, YALFIB, ZUMQUT) fulfilling all indicated criteria and only 5 out of 12 structures contained iodofluorobenzenes; these 5 structures were analyzed in Results and Discussion of this work. Computational details. The theoretical calculations including the full geometry optimization of model supramolecular adducts obtained from the experimental X-ray data followed by single point calculations for appropriate equilibrium structures and single point calculations based on the experimental X-ray geometries of model supramolecular adducts have been carried out at the DFT level of theory using the M06 functional81 with the help of Gaussian-0982 program package. The Douglas–Kroll–Hess 2nd order scalar relativistic calculations requested relativistic core Hamiltonian were carried out using the DZP-DKH basis sets83-86 for all atoms. No symmetry restrictions have been applied during the geometry optimization procedure. The Hessian matrices were calculated analytically for the equilibrium optimized structures of model supramolecular adducts in order to prove the location of correct minima (no imaginary frequencies). The topological analysis of the electron density distribution with the help of the atoms in molecules (QTAIM) method developed by Bader66 has been performed by using the Multiwfn program.87 The Wiberg bond indices were computed by using the natural bond orbital (NBO) partitioning scheme.88 The Cartesian atomic coordinates of model supramolecular adducts are presented in Supporting Information, Table S2. Details of Hirshfeld surface analysis. The Hirshfeld molecular surfaces for 1, 2, and 3 in Xray structures of 1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB), respectively, were generated by



Page 30 of 55

CrystalExplorer 3.1 program89-90 based on the results of the X-ray study. The normalized contact distances, dnorm,91 based on Bondi vdW radii,92 were mapped into the Hirshfeld surface. In the color scale, negative values of dnorm are visualized by the red color indicating contacts shorter than the sum of vdW radii. The white color denotes intermolecular distances close to vdW contacts with dnorm equal to zero. In turn, contacts longer than the sum of vdW radii with positive dnorm values are colored with blue.

5. Associated content The Supporting Information (PDF) contains: (i) crystallographic tables; (ii) figures of crystal packing of the adducts; (iii) contour line diagrams of the Laplacian distribution ∇2ρ(r), bond paths and selected zero-flux surfaces and RDG isosurface referring to noncovalent interactions; (iv) Cartesian atomic coordinates of model structures.

6. Acknowledgements The experimental part of this work was conducted under the Russian Science Foundation project 1413-00060. Theoretical calculations and the Hirshfeld surface analysis were supported by the Russian Foundation for Basic Research (project 17-03-00110) and RAS Program 1.14P (2018; coordinated by N.T. Kuznetsov), respectively. XRD studies were performed at the Center for X-ray Diffraction Studies of Saint Petersburg State University. The authors thank a reviewer for stimulating discussion on attribution of the observed weak interactions to lp–πh or tetrel bondings.


Page 31 of 55 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


References 1. Mahmudov, K. T.; Kopylovich, M. N.; da Silva, M.; Pombeiro, A. J. L., Non-covalent interactions in the synthesis of coordination compounds: Recent advances. Coord. Chem. Rev. 2017, 345, 54–72. 2. Cook, S. A.; Borovik, A. S., Molecular Designs for Controlling the Local Environments around Metal Ions. Acc. Chem. Res. 2015, 48, 2407–2414. 3. Mooibroek, T. J.; Gamez, P.; Reedijk, J., Lone pair–π interactions: a new supramolecular bond? CrystEngComm 2008, 10, 1501–1515. 4. Neel, A. J.; Hilton, M. J.; Sigman, M. S.; Toste, F. D., Exploiting non-covalent π interactions for catalyst design. Nature 2017, 543, 637. 5. Bauzá, A.; Mooibroek, T. J.; Frontera, A., The Bright Future of Unconventional σ/π-Hole Interactions. ChemPhysChem 2015, 16, 2496–2517. 6. Newberry, R. W.; Raines, R. T., The n→π* Interaction. Acc. Chem. Res. 2017, 50, 1838– 1846. 7. Bauza, A.; Sharko, A. V.; Senchyk, G. A.; Rusanov, E. B.; Frontera, A.; Domasevitch, K. V., π–hole interactions at work: crystal engineering with nitro-derivatives. CrystEngComm 2017, 19, 1933–1937. 8. Kukushkin, V. Y.; Bel'skii, V. K.; Aleksandrova, E. A.; Konovalov, V. E.; Kirakosyan, G. A., Platinum(IV)-mediated redox coupling of 2-propanone oximes in cis-[Pt(Me2C=NOH)2Cl4]. Crystal structure of [Pt(N(=O)CMe2ONCMe2)Cl2]. Inorg. Chem. 1992, 31, 3836-3840. 9. Politzer, P.; Murray, J. S., σ-holes and π-holes: Similarities and differences. J. Comput. Chem. 2018, 39, 464–471. 10. Fanfrlík, J.; Švec, P.; Růžičková, Z.; Hnyk, D.; Růžička, A.; Hobza, P., The Interplay between Various s- and p-Hole Interactions of Trigonal Boron and Trigonal Pyramidal Arsenic Triiodides. Crystals 2017, 7, 225. 11. Kozelka, J., Lone pair–π interactions in biological systems: occurrence, function, and physical origin. Eur. Biophys. J. 2017, 46, 729–737. 12. Wang, H.; Wang, W.; Jin, W. J., σ-Hole Bond vs π-Hole Bond: A Comparison Based on Halogen Bond. Chem. Rev. 2016, 116, 5072–5104. 13. Rosokha, S. V.; Kochi, J. K., Fresh Look at Electron-Transfer Mechanisms via the Donor/Acceptor Bindings in the Critical Encounter Complex. Acc. Chem. Res. 2008, 41, 641–653. 14. Calabrese, C.; Gou, Q.; Maris, A.; Caminati, W.; Melandri, S., Probing the Lone Pair•••πHole Interaction in Perfluorinated Heteroaromatic Rings: The Rotational Spectrum of Pentafluoropyridine•Water. J. Phys. Chem. Lett. 2016, 7, 1513–1517. 15. Singh, S. K.; Das, A., The n → π* interaction: a rapidly emerging non-covalent interaction. Phys. Chem. Chem. Phys. 2015, 17, 9596–9612. 16. Triguero, S.; Llusar, R.; Polo, V.; Fourmigué, M., Halogen Bonding Interactions of symTriiodotrifluorobenzene with Halide Anions: A Combined Structural and Theoretical Study. Cryst. Growth Des. 2008, 8, 2241–2247. 17. Chawla, M.; Chermak, E.; Zhang, Q.; Bujnicki, J. M.; Oliva, R.; Cavallo, L., Occurrence and stability of lone pair–π stacking interactions between ribose and nucleobases in functional RNAs. Nucleic Acids Res. 2017, 45, 11019–11032. 18. Pinalli, R.; Brancatelli, G.; Pedrini, A.; Menozzi, D.; Hernández, D.; Ballester, P.; Geremia, S.; Dalcanale, E., The Origin of Selectivity in the Complexation of N-Methyl Amino Acids by Tetraphosphonate Cavitands. J. Am. Chem. Soc. 2016, 138, 8569–8580. 19. Jin, J.; He, B.; Zhang, X.; Lin, H.; Wang, Y., SIRT2 Reverses 4-Oxononanoyl Lysine Modification on Histones. J. Am. Chem. Soc. 2016, 138, 12304–12307.



Page 32 of 55

20. Shah, M. B.; Liu, J.; Zhang, Q.; Stout, C. D.; Halpert, J. R., Halogen−π Interactions in the Cytochrome P450 Active Site: Structural Insights into Human CYP2B6 Substrate Selectivity. ACS Chemical Biology 2017, 12, 1204–1210. 21. Mooibroek, T. J., Coordinated nitrate anions can be directional π-hole donors in the solid state: a CSD study. CrystEngComm 2017, 19, 4485–4488. 22. Echeverría, J., Noncovalent Interactions in Succinic and Maleic Anhydride Derivatives. Cryst. Growth Des. 2018, 18, 506–512. 23. Saha, S.; Desiraju, G. R., σ-Hole and π-Hole Synthon Mimicry in Third-Generation Crystal Engineering: Design of Elastic Crystals. Chem. Eur. J. 2017, 23, 4936–4943. 24. Sun, H.; Horatscheck, A.; Martos, V.; Bartetzko, M.; Uhrig, U.; Lentz, D.; Schmieder, P.; Nazaré, M., Direct Experimental Evidence for Halogen–Aryl π-Interactions in Solution from Molecular Torsion Balances. Angew. Chem. Int. Ed. 2017, 56, 6454–6458. 25. Bretschneider, A.; Andrada, D. M.; Dechert, S.; Meyer, S.; Mata, R. A.; Meyer, F., Preorganized Anion Traps for Exploiting Anion-π Interactions: An Experimental and Computational Study. Chem. Eur. J. 2013, 19, 16988–17000. 26. Bushuyev, O. S.; Friscic, T.; Barrett, C. J., Photo-induced motion of azo dyes in organized media: from single and liquid crystals, to MOFs and machines. CrystEngComm 2016, 18, 7204– 7211. 27. Yi, H.; Albrecht, M.; Valkonen, A.; Rissanen, K., Perfluoro-1,1'-biphenyl and perfluoronaphthalene and their derivatives as π-acceptors for anions. New J. Chem. 2015, 39, 746– 749. 28. Giese, M.; Albrecht, M.; Valkonen, A.; Rissanen, K., The pentafluorophenyl group as πacceptor for anions: a case study. Chem. Sci. 2015, 6, 354–359. 29. Bushuyev, O. S.; Tomberg, A.; Vinden, J. R.; Moitessier, N.; Barrett, C. J.; Friscic, T., Azo•••phenyl stacking: a persistent self-assembly motif guides the assembly of fluorinated cisazobenzenes into photo-mechanical needle crystals. Chem. Commun. 2016, 52, 2103–2106. 30. Priimagi, A.; Cavallo, G.; Metrangolo, P.; Resnati, G., The Halogen Bond in the Design of Functional Supramolecular Materials: Recent Advances. Acc. Chem. Res. 2013, 46, 2686–2695. 31. Beale, T. M.; Chudzinski, M. G.; Sarwar, M. G.; Taylor, M. S., Halogen bonding in solution: thermodynamics and applications. Chem. Soc. Rev. 2013, 42, 1667–1680. 32. Brammer, L., Halogen bonding, chalcogen bonding, pnictogen bonding, tetrel bonding: origins, current status and discussion. Faraday Discuss. 2017, 203, 485–507. 33. Fourmigué, M.; Lieffrig, J., Organizing Radical Species in the Solid State with Halogen Bonding. Topics Current Chem. 2014, 91–113. 34. Zhu, W. G.; Zheng, R. H.; Zhen, Y. G.; Yu, Z. Y.; Dong, H. L.; Fu, H. B.; Shi, Q.; Hu, W. P., Rational Design of Charge-Transfer Interactions in Halogen-Bonded Co-crystals toward Versatile Solid-State Optoelectronics. J. Am. Chem. Soc. 2015, 137, 11038–11046. 35. Szell, P. M. J.; Gabriel, S. A.; Gill, R. D. D.; Wan, S. Y. H.; Gabidullin, B.; Bryce, D. L., 13C and 19F solid-state NMR and X-ray crystallographic study of halogen-bonded frameworks featuring nitrogen-containing heterocycles. Acta Cryst. Sect. C 2017, 73, 157–167. 36. Choquesillo-Lazarte, D.; Nemec, V.; Cincic, D., Halogen bonded cocrystals of active pharmaceutical ingredients: pyrazinamide, lidocaine and pentoxifylline in combination with haloperfluorinated compounds. CrystEngComm 2017, 19, 5293–5299. 37. Torubaev, Y. V.; Skabitskiy, I. V.; Rusina, P.; Pasynskii, A. A.; Rai, D. K.; Singh, A., Organometallic halogen bond acceptors: directionality, hybrid cocrystal precipitation, and blueshifted CO ligand vibrational band. CrystEngComm 2018, 20, 2258–2266. 38. Syssa-Magale, J.-L.; Boubekeur, K.; Palvadeau, P.; Meerschaut, A.; Schollhorn, B., The tailoring of crystal structures via the self-assembly of organic coordination compounds by N•••I


Page 33 of 55 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


non-covalent halogen bonds: co-crystals of sterically hindered N-heterocycles and 1,4-diiodotetrafluorobenzene. CrystEngComm 2005, 7, 302–308. 39. Eccles, K. S.; Morrison, R. E.; Stokes, S. P.; O’Mahony, G. E.; Hayes, J. A.; Kelly, D. M.; O’Boyle, N. M.; Fábián, L.; Moynihan, H. A.; Maguire, A. R.; Lawrence, S. E., Utilizing Sulfoxide•••Iodine Halogen Bonding for Cocrystallization. Cryst. Growth Des. 2012, 12, 2969– 2977. 40. Bikbaeva, Z. M.; Ivanov, D. M.; Novikov, A. S.; Ananyev, I. V.; Bokach, N. A.; Kukushkin, V. Y., Electrophilic–Nucleophilic Dualism of Nickel(II) toward Ni•••I Noncovalent Interactions: Semicoordination of Iodine Centers via Electron Belt and Halogen Bonding via σ-Hole. Inorg. Chem. 2017, 56, 13562–13578. 41. Li, L.; Wang, H.; Wang, W.; Jin, W. J., Interactions between haloperfluorobenzenes and fluoranthene in luminescent cocrystals from π-hole•••π to σ-hole•••π bonds. CrystEngComm 2017, 19, 5058–5067. 42. Ji, B.; Wang, W.; Deng, D.; Zhang, Y.; Cao, L.; Zhou, L.; Ruan, C.; Li, T., Structural competition between p•••p interactions and halogen bonds: a crystallographic study. CrystEngComm 2013, 15, 769–774. 43. Bikbaeva, Z. M.; Novikov, A. S.; Suslonov, V. V.; Bokach, N. A.; Kukushkin, V. Y., Metalmediated reactions between dialkylcyanamides and acetamidoxime generate unusual (nitrosoguanidinate)nickel(II) complexes. Dalton Trans. 2017, 46, 10090–10101. 44. Bondi, A., van der Waals Volumes and Radii. J. Phys. Chem. 1964, 68, 441–451. 45. Desiraju Gautam, R.; Ho, P. S.; Kloo, L.; Legon Anthony, C.; Marquardt, R.; Metrangolo, P.; Politzer, P.; Resnati, G.; Rissanen, K., Definition of the halogen bond (IUPAC Recommendations 2013). In Pure and Applied Chemistry, 2013; Vol. 85, p 1711. 46. Kadiyala, R. R.; Tilly, D.; Nagaradja, E.; Roisnel, T.; Matulis, V. E.; Ivashkevich, O. A.; Halauko, Y. S.; Chevallier, F.; Gros, P. C.; Mongin, F., Computed CH Acidity of Biaryl Compounds and Their Deprotonative Metalation by Using a Mixed Lithium/Zinc-TMP Base. Chem. Eur. J. 2013, 19, 7944-7960. 47. Brown, J. J.; Brock, A. J.; Pfrunder, M. C.; Sarju, J. P.; Perry, A. Z.; Whitwood, A. C.; Bruce, D. W.; McMurtrie, J. C.; Clegg, J. K., Co-Crystallisation of 1,4-Diiodotetrafluorobenzene with Three Different Symmetric Dipyridylacetylacetone Isomers Produces Four Halogen-Bonded Architectures. Aust. J. Chem. 2017, 70, 594–600. 48. Johnson, M. T.; Dzolic, Z.; Cetina, M.; Wendt, O. F.; Ohrstrom, L.; Rissanen, K., Neutral Organometallic Halogen Bond Acceptors: Halogen Bonding in Complexes of PCPPdX (X = Cl, Br, I) with Iodine (I2), 1,4-Diiodotetrafluorobenzene (F4DIBz), and 1,4-Diiodooctafluorobutane (F8DIBu). Cryst. Growth Des. 2012, 12, 362–368. 49. d'Agostino, S.; Grepioni, F.; Braga, D.; Ventura, B., Tipping the Balance with the Aid of Stoichiometry: Room Temperature Phosphorescence versus Fluorescence in Organic Cocrystals. Cryst. Growth Des. 2015, 15, 2039–2045. 50. Yan, D.; Yang, H.; Meng, Q.; Lin, H.; Wei, M., Two-Component Molecular Materials of 2,5-Diphenyloxazole Exhibiting Tunable Ultraviolet/Blue Polarized Emission, Pump-enhanced Luminescence, and Mechanochromic Response. Adv. Funct. Mater. 2014, 24, 587–594. 51. Serpell, C. J.; Thomas, O.; Odell, B.; Claridge, T. D. W.; Chall, R.; Thompson, A. L.; Beer, P. D., Dimeric self-association of an isophthalamide macrocycle in solution and the solid state. CrystEngComm 2011, 13, 4586–4591. 52. Zbačnik, M.; Vitković, M.; Vulić, V.; Nogalo, I.; Cinčić, D., Competition between Halogen Bonds in Cocrystals of Imines Derived from o-Vanillin. Cryst. Growth Des. 2016, 16, 6381–6389.



Page 34 of 55

53. Korenaga, T.; Tanaka, H.; Ema, T.; Sakai, T., Intermolecular oxygen atom•••π interaction in the crystal packing of chiral amino alcohol bearing a pentafluorophenyl group. J. Fluorine Chem. 2003, 122, 201–205. 54. Korenaga, T.; Shoji, T.; Onoue, K.; Sakai, T., Demonstration of the existence of intermolecular lone pair•••π interaction between alcoholic oxygen and the C6F5 group in organic solvent. Chem. Commun. 2009, 4678–4680. 55. Benaglia, M.; Cozzi, F.; Mancinelli, M.; Mazzanti, A., The Intramolecular Interaction of Thiophene and Furan with Aromatic and Fluoroaromatic Systems in Some [3.3]Meta(heterocyclo)paracyclophanes: A Combined Computational and NMR Spectroscopic Study. Chem. Eur. J. 2010, 16, 7456–7468. 56. Bauzá, A.; Terrón, A.; Barceló-Oliver, M.; García-Raso, A.; Frontera, A., On the importance of antiparallel CO⋯C–F interactions in N1-(3-hydroxypropyl)-5-fluorouracilate–Hg(II) complex: A combined X-ray and DFT study. Inorg. Chim. Acta 2016, 452, 244-250. 57. Barceló-Oliver, M.; Estarellas, C.; García-Raso, A.; Terrón, A.; Frontera, A.; Quiñonero, D.; Mata, I.; Molins, E.; Deyà, P. M., Experimental and theoretical study of uracil derivatives: the crucial role of weak fluorine–fluorine noncovalent interactions. CrystEngComm 2010, 12, 37583767. 58. Freire, M. G.; Carvalho, P. J.; Santos, L. M. N. B. F.; Gomes, L. R.; Marrucho, I. M.; Coutinho, J. A. P., Solubility of water in fluorocarbons: Experimental and COSMO-RS prediction results. J. Chem. Thermodyn. 2010, 42, 213–219. 59. Rowland, R. S.; Taylor, R., Intermolecular Nonbonded Contact Distances in Organic Crystal Structures: Comparison with Distances Expected from van der Waals Radii. J. Phys. Chem. 1996, 100, 7384-7391. 60. Braga, D.; Grepioni, F.; Desiraju, G. R., Crystal Engineering and Organometallic Architecture. Chem. Rev. 1998, 98, 1375-1406. 61. Matsumoto, A.; Tanaka, T.; Tsubouchi, T.; Tashiro, K.; Saragai, S.; Nakamoto, S., Crystal Engineering for Topochemical Polymerization of Muconic Esters Using Halogen−Halogen and CH/π Interactions as Weak Intermolecular Interactions. J. Am. Chem. Soc. 2002, 124, 8891-8902. 62. Childs, S. L.; Stahly, G. P.; Park, A., The Salt−Cocrystal Continuum: The Influence of Crystal Structure on Ionization State. Mol. Pharm. 2007, 4, 323-338. 63. Bauzá, A.; Mooibroek, T. J.; Frontera, A., The Bright Future of Unconventional σ/π-Hole Interactions. ChemPhysChem 2015, 16, 2496-2517. 64. Politzer, P.; Murray, J. S.; Clark, T. J., Mathematical modeling and physical reality in noncovalent interactions. J. Mol. Model. 2015, 21, 52. 65. Desiraju, G. R.; Ho, P. S.; Kloo, L.; Legon, A. C.; Marquardt, R.; Metrangolo, P.; Politzer, P.; Resnati, G.; Rissanen, K., Definition of the halogen bond (IUPAC Recommendations 2013). Pure Appl. Chem. 2013, 85, 1711–1713. 66. Bader, R. F. W., A quantum theory of molecular structure and its applications. Chem. Rev. 1991, 91, 893–928. 67. Adonin, S. A.; Gorokh, I. D.; Novikov, A. S.; Abramov, P. A.; Sokolov, M. N.; Fedin, V. P., Halogen Contacts-Induced Unusual Coloring in BiIII Bromide Complex: Anion-to-Cation Charge Transfer via Br•••Br Interactions. Chem. Eur. J. 2017, 23, 15612–15616. 68. Mikherdov, A. S.; Kinzhalov, M. A.; Novikov, A. S.; Boyarskiy, V. P.; Boyarskaya, I. A.; Dar’in, D. V.; Starova, G. L.; Kukushkin, V. Y., Difference in Energy between Two Distinct Types of Chalcogen Bonds Drives Regioisomerization of Binuclear (Diaminocarbene)PdII Complexes. J. Am. Chem. Soc. 2016, 138, 14129–14137. 69. Ivanov, D. M.; Novikov, A. S.; Ananyev, I. V.; Kirina, Y. V.; Kukushkin, V. Y., Halogen bonding between metal centers and halocarbons. Chem. Commun. 2016, 52, 5565−5568.


Page 35 of 55 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


70. Kinzhalov, M. A.; Kashina, M. V.; Mikherdov, A. S.; Mozheeva, E. A.; Novikov, A. S.; Smirnov, A. S.; Ivanov, D. M.; Kryukova, M. A.; Ivanov, A. Y.; Smirnov, S. N.; Kukushkin, V. Y.; Luzyanin, K. V., Solubility of halide-containing organometallics is dramatically enhanced in diiodomethane: can the solvent•••complex halogen bonding be held responsible? Angew. Chem. Int. Ed. 2018, 57, 12785–12789. 71. Johnson, E. R.; Keinan, S.; Mori-Sánchez, P.; Contreras-García, J.; Cohen, A. J.; Yang, W., Revealing Noncovalent Interactions. J. Am. Chem. Soc. 2010, 132, 6498–6506. 72. Espinosa, E.; Molins, E.; Lecomte, C., Hydrogen bond strengths revealed by topological analyses of experimentally observed electron densities. Chem. Phys. Lett. 1998, 285, 170–173. 73. Vener, M. V.; Egorova, A. N.; Churakov, A. V.; Tsirelson, V. G., Intermolecular hydrogen bond energies in crystals evaluated using electron density properties: DFT computations with periodic boundary conditions. J. Comput. Chem. 2012, 33, 2303–2309. 74. Bartashevich, E. V.; Tsirelson, V. G., Interplay between non-covalent interactions in complexes and crystals with halogen bonds Russ. Chem. Rev. 2014, 83, 1181–1203. 75. Espinosa, E.; Alkorta, I.; Elguero, J.; Molins, E., From weak to strong interactions: A comprehensive analysis of the topological and energetic properties of the electron density distribution involving X–H•••F–Y systems. J. Chem. Phys. 2002, 117, 5529–5542. 76. Gao, H.; Zhao, X.; Wang, H.; Pang, X.; Jin, W., Cocrystal Assembled by 1,2Diiodotetrafluorobenzene and Acridine via C–I•••N Halogen Bond and π-hole•••F Bonds. Chin. J. Chem. 2013, 31, 1279–1284. 77. Ma, N.; Zhang, Y.; Ji, B.; Tian, A.; Wang, W., Structural Competition between Halogen Bonds and Lone-Pair•••π Interactions in Solution. ChemPhysChem 2012, 13, 1411–1414. 78. Lu, Y.; Liu, Y.; Li, H.; Zhu, X.; Liu, H.; Zhu, W., Energetic Effects between Halogen Bonds and Anion-p or Lone Pair-p Interactions: A Theoretical Study. J. Phys. Chem. A 2012, 116, 2591– 2597. 79. Dolomanov, O. V.; Bourhis, L. J.; Gildea, R. J.; Howard, J. A. K.; Puschmann, H., OLEX2: A Complete Structure Solution, Refinement and Analysis Program. J. Appl. Crystallogr. 2009, 42, 339−341. 80. Sheldrick, G. M., Crystal structure refinement with SHELXL. Acta Cryst. Sect. C 2015, 71, 3–8. 81. Zhao, Y.; Truhlar, D. G., The M06 suite of density functionals for main group thermochemistry, thermochemical kinetics, noncovalent interactions, excited states, and transition elements: two new functionals and systematic testing of four M06-class functionals and 12 other functionals. Theor. Chem. Acc. 2008, 120, 215–241. 82. Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb, M. A.; Cheeseman, J. R.; Scalmani, G.; Barone, V.; Mennucci, B.; Petersson, G. A.; Nakatsuji, H.; Caricato, M.; Li, X.; Hratchian, H. P.; Izmaylov, A. F.; Bloino, J.; Zheng, G.; Sonnenberg, J. L.; Hada, M.; Ehara, M.; Toyota, K.; Fukuda, R.; Hasegawa, J.; Ishida, M.; Nakajima, T.; Honda, Y.; Kitao, O.; Nakai, H.; Vreven, T.; A.;, M. J.; Peralta, J. E.; Ogliaro, F.; Bearpark, M.; Heyd, J. J.; Brothers, E.; Kudin, K. N.; Staroverov, V. N.; Keith, T.; Kobayashi, R.; Normand, J.; Raghavachari, K.; Rendell, A.; Burant, J. C.; Iyengar, S. S.; Tomasi, J.; Cossi, M.; Rega, N.; Millam, J. M.; Klene, M.; Knox, J. E.; Cross, J. B.; Bakken, V.; Adamo, C.; Jaramillo, J.; Gomperts, R.; Stratmann, R. E.; Yazyev, O.; Austin, A. J.; Cammi, R.; Pomelli, C.; Ochterski, J. W.; Martin, R. L.; Morokuma, K.; Zakrzewski, V. G.; Voth, G. A.; Salvador, P.; Dannenberg, J. J.; Dapprich, S.; Daniels, A. D.; Farkas, O.; Foresman, J. B.; Ortiz, J. V.; J.;, C.; Fox, D. J., Gaussian 09, Revision C.01 Gaussian, Inc. Wallingford CT, 2010. 83. Barros, C. L.; de Oliveira, P. J. P.; Jorge, F. E.; Neto, A. C.; Campos, M., Gaussian basis set of double zeta quality for atoms Rb through Xe: application in non-relativistic and relativistic calculations of atomic and molecular properties. Mol. Phys. 2010, 108, 1965–1972.



Page 36 of 55

84. Neto, A. C.; Jorge, F. E., All-electron double zeta basis sets for the most fifth-row atoms: Application in DFT spectroscopic constant calculations. Chem. Phys. Lett. 2013, 582, 158–162. 85. de Berrêdo, R. C.; Jorge, F. E., All-electron double zeta basis sets for platinum: Estimating scalar relativistic effects on platinum(II) anticancer drugs. J. Mol. Struct.-THEOCHEM 2010, 961, 107–112. 86. Jorge, F. E.; Neto, A. C.; Camiletti, G. G.; Machado, S. F., Contracted Gaussian basis sets for Douglas-Kroll-Hess calculations: Estimating scalar relativistic effects of some atomic and molecular properties. J. Chem. Phys. 2009, 130, 064108. 87. Lu, T.; Chen, F. W., Multiwfn: A multifunctional wavefunction analyzer. J. Comput. Chem. 2012, 33, 580–592. 88. Glendening, E. D.; Landis, C. R.; Weinhold, F., Natural bond orbital methods. WIREs Comput. Mol. Sci. 2012, 2, 1–42. 89. Spackman, M. A.; Jayatilaka, D., Hirshfeld surface analysis. CrystEngComm 2009, 11, 19– 32. 90. Wolff, S. K.; Grimwood, D. J.; McKinnon, J. J.; Turner, M. J.; Jayatilaka, D.; Spackman, M. A. CrystalExplorer (Version 3.1) University of Western Australia, 2012. 91. McKinnon, J. J.; Jayatilaka, D.; Spackman, M. A., Towards quantitative analysis of intermolecular interactions with Hirshfeld surfaces. Chem. Commun. 2007, 3814–3816. 92. Bondi, A., van der Waals Volumes and Radii of Metals in Covalent Compounds. J. Phys. Chem. 1966, 70, 3006–3007.


Page 37 of 55 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


For Table of Contents Use Only Noncovalent Interactions Involving Iodofluorobenzenes: The Interplay of Halogen Bonding and Weak lp(O)•••π-Holearene Interactions

Alexander S. Novikov, Daniil M. Ivanov, Zarina M. Bikbaeva, Nadezhda A. Bokach, Vadim Yu. Kukushkin

An unreported noncovalent bonding pattern for iodofluorobenzenes belongs to lone pair(O)–π hole interactions, lp(O)–πh, supported by halogen bonding, is revealed.


Crystal Growth & Design 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

ACS Paragon Plus Environment

Page 38 of 55

Page 39 of 55

Nu

••

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


F

F

R

R a2

••

Nu

F

F R R'

R c2

E+

b2

E+

R'

R'

R' R'

F

R

e2

••

Nu d2

Unknown bonding pattern when Nu ≠ Halogen ACS Paragon Plus Environment

R'



Page 40 of 55

Page 41 of 55 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23



Crystal Growth & Design 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


Page 42 of 55

Page 43 of 55 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



Crystal Growth Page& 44 Design of 55

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 ACS Paragon Plus Environment 19 20 21

X

Page 45 of 55 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

H NRR'

O

N N

X = F, I

N Ni

N O

N

F

X

X I

X


F

X

O

H (CH2)5N

N

N N

NRR'

H

N Ni

N O

I

H


1•(1,4-FIB), 2•2(1,3,5-FIB), and 3•2(1,4-FIB)

F F

N

N

3•2(1,4-FIB)

I

N(CH2)5

MeO


MeO 1 2 3 4 5 6 7 8

N N

I

N

I

N

MeO

Page 46 of 55

O Me


R

R

Page 47 of 55


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 48 of 55

Page 49 of 55 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21



Crystal Growth & Design 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


Page 50 of 55

Page 51 of 55 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



Crystal Growth & Design 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15


Page 52 of 55

Page 53 of 55


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


I

I


F 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Page 54 of 55

Y

F F

F

F

F

F F

F

F

F F

I

I a16

I F

Y − solvent ACS Paragon Plus Environment

b16

Y

Page 55 of 55

F

F

R

R

••

a17

••

Nu

E+

Nu


b17

Nu

••

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23


Noncovalent Interactions Involving Iodofluorobenzenes: The Interplay

Recommend Documents