Anion Templated Crystal Engineering of Halogen Bonding Tripodal Tris(halopyridinium) Compounds

Author(s):  
Emer Foyle ◽  
Nicholas White

<div>In this work four new tripodal tris(halopyridinium) receptors containing potentially halogen</div><div>bonding groups were prepared. The ability of the receptors to bind anions in competitive</div><div>CD<sub>3</sub>CN/d<sub>6</sub>-DMSO was studied using <sup>1</sup>H NMR titration experiments, which revealed that the</div><div>receptors bind chloride anions more strongly than more basic acetate or other halide ions.</div><div>The solid state self–assembly of the tripodal receptors with halide anions was investigated by</div><div>X-ray crystallography. The nature of the structures was dependent on the choice of halide</div><div>anion, as well as the crystallisation solvent. Halogen bond lengths as short as 80% of the sum</div><div>of the van der Waals radii were observed, which is shorter than any halogen bonds involving</div><div>halopyridinium receptors in the Cambridge Structural Database.</div>

2020 ◽  
Author(s):  
Emer Foyle ◽  
Nicholas White

<div>In this work four new tripodal tris(halopyridinium) receptors containing potentially halogen</div><div>bonding groups were prepared. The ability of the receptors to bind anions in competitive</div><div>CD<sub>3</sub>CN/d<sub>6</sub>-DMSO was studied using <sup>1</sup>H NMR titration experiments, which revealed that the</div><div>receptors bind chloride anions more strongly than more basic acetate or other halide ions.</div><div>The solid state self–assembly of the tripodal receptors with halide anions was investigated by</div><div>X-ray crystallography. The nature of the structures was dependent on the choice of halide</div><div>anion, as well as the crystallisation solvent. Halogen bond lengths as short as 80% of the sum</div><div>of the van der Waals radii were observed, which is shorter than any halogen bonds involving</div><div>halopyridinium receptors in the Cambridge Structural Database.</div>


Inorganics ◽  
2019 ◽  
Vol 7 (10) ◽  
pp. 119 ◽  
Author(s):  
Hardin ◽  
Ellington ◽  
Nguyen ◽  
Rheingold ◽  
Tschumper ◽  
...  

Two new aromatic pyrimidine-based derivatives designed specifically for halogen bond directed self-assembly are investigated through a combination of high-resolution Raman spectroscopy, X-ray crystallography, and computational quantum chemistry. The vibrational frequencies of these new molecular building blocks, pyrimidine capped with furan (PrmF) and thiophene (PrmT), are compared to those previously assigned for pyrimidine (Prm). The modifications affect only a select few of the normal modes of Prm, most noticeably its signature ring breathing mode, ν1. Structural analyses afforded by X-ray crystallography, and computed interaction energies from density functional theory computations indicate that, although weak hydrogen bonding (C–H···O or C–H···N interactions) is present in these pyrimidine-based solid-state co-crystals, halogen bonding and π-stacking interactions play more dominant roles in driving their molecular-assembly.


Crystals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1075
Author(s):  
Cody Loy ◽  
Matthias Zeller ◽  
Sergiy V. Rosokha

The wide-range variation of the strength of halogen bonds (XB) not only facilitates a variety of applications of this interaction, but it also allows examining the relation (and interconversion) between supramolecular and covalent bonding. Herein, the Br…Cl halogen bonding in a series of complexes of bromosubstituted electrophiles (R-Br) with chloride anions were examined via X-ray crystallographic and computational methods. Six co-crystals showing such bonding were prepared by evaporation of solutions of R-Br and tetra-n-propylammonium chloride or using Cl− anions released in the nucleophilic reaction of 1,4-diazabicyclo[2.2.2]octane with dichloromethane in the presence of R-Br. The co-crystal comprised networks formed by 3:3 or 2:2 halogen bonding between R-Br and Cl−, with the XB lengths varying from 3.0 Å to 3.25 Å. Analysis of the crystallographic database revealed examples of associations with substantially longer and shorter Br…Cl separations. DFT computations of an extended series of R–Br…Cl− complexes confirmed that the judicious choice of brominated electrophile allows varying halogen Br…Cl bond strength and length gradually from the values common for the weak intermolecular complexes to that approaching a fully developed covalent bond. This continuity of halogen bond strength in the experimental (solid-state) and calculated associations indicates a fundamental link between the covalent and supramolecular bonding.


2017 ◽  
Vol 73 (10) ◽  
pp. 803-809 ◽  
Author(s):  
Ai Wang ◽  
Ulli Englert

Specific short contacts are important in crystal engineering. Hydrogen bonds have been particularly successful and together with halogen bonds can be useful for assembling small molecules or ions into crystals. The ionic constituents in the isomorphous 3,5-dichloropyridinium (3,5-diClPy) tetrahalometallates 3,5-dichloropyridinium tetrachloridozincate(II), (C5H4Cl2N)2[ZnCl4] or (3,5-diClPy)2ZnCl4, 3,5-dichloropyridinium tetrabromidozincate(II), (C5H4Cl2N)2[ZnBr4] or (3,5-diClPy)2ZnBr4, and 3,5-dichloropyridinium tetrabromidocobaltate(II), (C5H4Cl2N)2[CoBr4] or (3,5-diClPy)2CoBr4, arrange according to favourable electrostatic interactions. Cations are preferably surrounded by anions and vice versa; rare cation–cation contacts are associated with an antiparallel dipole orientation. N—H...X (X = Cl and Br) hydrogen bonds and X...X halogen bonds compete as closest contacts between neighbouring residues. The former dominate in the title compounds; the four symmetrically independent pyridinium N—H groups in each compound act as donors in charge-assisted hydrogen bonds, with halogen ligands and the tetrahedral metallate anions as acceptors. The M—X coordinative bonds in the latter are significantly longer if the halide ligand is engaged in a classical X...H—N hydrogen bond. In all three solids, triangular halogen-bond interactions are observed. They might contribute to the stabilization of the structures, but even the shortest interhalogen contacts are only slightly shorter than the sum of the van der Waals radii.


RSC Advances ◽  
2015 ◽  
Vol 5 (100) ◽  
pp. 82544-82548 ◽  
Author(s):  
Jamey Wilson ◽  
Jon Steven Dal Williams ◽  
Chesney Petkovsek ◽  
Peyton Reves ◽  
Jonah W. Jurss ◽  
...  

The use of a thiophene-based building block (Pyr-T) to achieve a supramolecular assembly driven by halogen bonding (XB) is described. X-ray crystallography, NMR, Raman spectroscopy, and computational chemistry afford evidence of strong XB and π–π stacking.


2018 ◽  
Vol 22 (09n10) ◽  
pp. 944-952 ◽  
Author(s):  
Fen Li ◽  
Yongjie Zhang ◽  
Lina Zhou ◽  
Xin Zhang ◽  
Zhijian Chen

Two boron-dipyrromethene dyes bearing a conjugated guanine unit (G-BODIPYs) 1 and 2 were synthesized and fully characterized. The self-assembly properties of these dyes were investigated by X-ray crystallography, [Formula: see text]H NMR and UV-vis spectroscopy. As revealed by X-ray crystal structure studies, G-BODIPY 1 self-assembled into ribbon-like structures due to the intermolecular hydrogen bonding and [Formula: see text]–[Formula: see text] stacking interaction. Concentration-dependent [Formula: see text]H NMR experiments confirmed the formation of hydrogen bonds of the guanine units in solution for both dye 1 and 2. In the presence of K[Formula: see text], the characteristic signals for the formation of cyclic G-quadruplex structures were observed in the [Formula: see text]H NMR study. Aggregation of G-BODIPY dyes was further monitored by UV-vis absorption spectroscopy by varying the solvent polarity and temperature. H-type aggregates of dye 1, which was characterized by a new hypsochromically shifted absorption band with [Formula: see text] 461 nm, was obtained. In the presence of K[Formula: see text], the enhancement of stability was observed for the H-aggregates of dye 1.


Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3305 ◽  
Author(s):  
Carolina von Essen ◽  
Kari Rissanen ◽  
Rakesh Puttreddy

Two series of 2,5-dihalopyridine-Cu(I)A (A = I, Br) complexes based on 2-X-5-iodopyridine and 2-X-5-bromopyridine (X = F, Cl, Br and I) are characterized by using single-crystal X-ray diffraction analysis to examine the nature of C2−X2···A–Cu and C5−X5···A–Cu halogen bonds. The reaction of the 2,5-dihalopyridines and Cu(I) salts allows the synthesis of eight 1-D coordination polymers and a discrete structure. The resulting Cu(I)-complexes are linked by C−X···A–Cu halogen bonds forming 3-D supramolecular networks. The C−X···A–Cu halogen bonds formed between halopyridine ligands and copper(I)-bound halide ions are stronger than C−X···X’–C interactions between two 2,5-dihalopyridine ligands. The C5−I5···I–Cu and C5−Br5···Br–Cu halogens bonds are shorter for C2-fluorine than C2-chlorine due to the greater electron-withdrawing power of fluorine. In 2,5-diiodopyridine-Cu(I)Br complex, the shorter C2−I2···Br–Cu [3.473(5) Å] distances are due to the combined polarization of C2-iodine by C2−I2···Cu interactions and para-electronic effects offered by the C5-iodine, whilst the long halogen bond contacts for C5−I5···Br–Cu [3.537(5) Å] are indicative that C2-iodine has a less para-electronic influence on the C5-iodine. In 2-fluoro-5-X-pyridine-Cu(I) complexes, the C2-fluorine is halogen bond passive, while the other C2-halogens in 2,5-dihalopyridine-Cu(I), including C2-chlorine, participate in halogen bonding interactions.


2017 ◽  
Vol 73 (1) ◽  
pp. 2-8 ◽  
Author(s):  
Chideraa I. Nwachukwu ◽  
Nathan P. Bowling ◽  
Eric Bosch

Halogen bonding is a well-established and intensively studied intermolecular interaction that has also been used in the preparation of functional materials. While polyfluoroiodo- and polyfluorobromobenzenes have been widely used as aromatic halogen-bond donors, there have been very few studies of iodoimidazoles with regard to halogen bonding. We describe here the X-ray structures of three iodoimidazole derivatives, namely 1-benzyl-2-iodo-1H-imidazole, C10H9IN2, (1), 1-benzyl-4-iodo-1H-imidazole, C10H9IN2, (2), and 1-benzyl-2-iodo-1H-benzimidazole, C14H11IN2, (3), and the halogen bonds that dominate the intermolecular interactions in each of these three structures. The three-dimensional structure of (1) is dominated by a strong C—I...N halogen bond, with an N...I distance of 2.8765 (2) Å, that connects the molecules into one-dimensional zigzag ribbons of molecules. In contrast, the three-dimensional structures of (2) and (3) both feature C—I...π halogen-bonded dimers.


2020 ◽  
Author(s):  
Si Yuan Cheng ◽  
Wei Wei Zhao ◽  
Xi Nan Yang ◽  
Lian Tong Wei ◽  
Zhu Tao ◽  
...  

Abstract Binding behaviors between CyP 6 Q[6] and three have been investigated by means of X-ray crystallography, 1 H NMR spectroscopy,amino acids and isothermal titration calorimetry (ITC). The results showed that CyP 6 Q[6] forms a 1:2 inclusion complex with glycine, but 1:1 complexes with both leucine and lysine. Whereas the carboxyl group of glycine can enter the interior of the cavity of CyP6Q[6], only the alkyl chains of leucine and lysine can enter this cavity. Interestingly, leucine can adopt two different self-assembly modes upon its interaction with cucurbituril, depending on the external conditions, whereas glycine and lysine do not exhibit such behavior.


Author(s):  
Kavitha Buntara Sanjeeva ◽  
Ilaria Tirotta ◽  
Vijith Kumar ◽  
Francesca Baldelli Bombelli ◽  
Giancarlo Terraneo ◽  
...  

The synthesis and self-assembly capabilities of a new halogen-bond donor ligand, 2,3,5,6-tetrafluoro-4-iodophenyl 5-(1,2-dithiolan-3-yl)pentanoate (1), are reported. The crystal structure of ligand (1) and the formation of a cocrystal with 1,2-di(4-pyridyl)ethylene, (1)·(2), both show halogen bonds involving the 4-iodotetrafluorobenzene moiety. Ligand (1), being a self-complementary unit, forms an infinite halogen-bonded chain driven by the S...I synthon, while the cocrystal (1)·(2) self-assembles into a discrete trimeric entity driven by the N...I synthon. Ligand (1) was also successfully used to functionalize the surface of gold nanoparticles, AuNP-(1). Experiments on the dispersibility profile of AuNP-(1) demonstrated the potential of halogen bonding in facilitating the dispersion of modified NPs with halogen-bond donors in pyridine.


Sign in / Sign up

Export Citation Format

Share Document