Wechselwirkungen in Molekülkristallen, 168 [1,2]. σ-Donator/Akzeptor-Komplexe {HCl3···Xe⊖ }(X⊖ = Cl, Br⊖ , I⊖ ) von Triiodmethan in Tetraphenylphosphoniumhalogeniden / Interaction in Molecular Crystals, 168 [1, 2]. σ-Donor/Acceptor Complexes {HCl3 ···X⊖} (X⊖ = Cl⊖ , Br⊖ , I⊖ ) of Triiodomethane in Tetraphenylphosphonium Halides

2001 ◽  
Vol 56 (2) ◽  
pp. 152-163 ◽  
Author(s):  
Hans Bock ◽  
Sven Holl
Keyword(s):  
Low Temperature ◽  
Crystal Packing ◽  
Molecular Crystals ◽  
Cambridge Structural Database ◽  
Halide Anion ◽  
Structure Comparison ◽  
Halogen Compounds ◽  
Donor Acceptor ◽  
Structural Database ◽  
Halide Salts

AbstractThree donor/acceptor complexes between halide anion donors and the triiodomethane acceptor with tetraphenylphosphonium countercations, {(H5C6)4P⊕ X⊖ ··· I3CH)} (X⊖ = Cl⊖ , Br⊖, I⊖ ) could be crystallized and their structures determined at low temperature. Their crystal packing motifs are donor/acceptor layers of halide anion/triiodomethane patterns and phenyl/ phenyl interacting tetraphenylphosphonium cation chains. Structure comparison and discussion are based on literature-known analogous adducts with organoammonium salts as well as the phenyl/phenyl interactions in the numerous tetraphenylphosphonium salts registered in the Cambridge Structural Database. The results add novel facets to the selforganization phenomena observed on crystallization of halogen compounds and halide salts.

Wechselwirkungen in Molekülkristallen, 179 [1, 2]. σ-Donator/Akzeptor-Komplexe {I2C=CI2···X⊖ } (X⊖ = Cl⊖ , Br⊖ , I⊖ , SCN⊖ ) von Tetraiodethen in Tetra(n-butyl)ammoniumhalogenid-Salzen / Interaction in Molecular Crystals, 179 [1, 2]. σ-Donor/Acceptor Complexes {I2C=CI2···X⊖} (X⊖= Cl⊖, Br⊖, I⊖, SCN⊖) of Tetraiodoethene in Tetra(n-butyl)ammonium Halide Salts

2002 ◽  
Vol 57 (7) ◽  
pp. 713-725 ◽  
Author(s):  
Hans Bock ◽  
Sven Holl
Keyword(s):  
Low Temperature ◽  
Self Assembly ◽  
Molecular Crystals ◽  
Database Search ◽  
Acceptor Molecule ◽  
Halide Anion ◽  
Structure Comparison ◽  
Donor Acceptor ◽  
Structural Database ◽  
Halide Salts

Four donor/acceptor complexes between halide anion donors and the tetraiodoethene acceptor molecule with tetra(n-butyl)ammoniumcountercations, {(H9C4)4N⊕X⊖···I2C=CI2)} (X⊖ = Cl⊖, Br⊖, I⊖, SCN⊖) could be crystallized from acetone solutions of the components R4N⊕X⊖ and I2C=CI2 by using low gradient techniques, and their structures determined at low temperature. Their molecule packing motif are layers of halide anion/tetraiodoethene patterns, which are penetrated by one of the four R4N⊕ n-butyl chains. The structure comparison, including analogous ones from an extensive Cambridge Structural Database search, discusses the geminal or vicinal addition to dimer subunits {X⊖···I2C=CI2}2 as well as their ribbon formation via additional contacts X⊖···I, and the effects of the voluminous R4N⊕ countercations. Altogether some light is shedded on essential facets of the fascinating self-assembly comprising an electron-rich halide anion and a polyiodo acceptor molecule.

Wechselwirkungen in Molekülkristallen, 180 [1, 2]. σ-Donator/Akzeptor-Komplexe {S(CI)4···X⊖ }(X⊖ = I⊖ , SCN⊖ ) von Tetraiodthiophen in Tetra(n-butyl)ammoniumhalogenid-Salzen/Interaction in Molecular Crystals, 180 [1, 2]. -Donor/Acceptor Complexes {S(CI)4···X⊖} (X⊖= I⊖, SCN⊖ of Tetraiodothiophene in Tetra(n-butyl)ammonium Halide Salts

2002 ◽  
Vol 57 (8) ◽  
pp. 835-842 ◽  
Author(s):  
Hans Bock ◽  
Sven Holl
Keyword(s):  
Low Temperature ◽  
Self Assembly ◽  
Molecular Crystals ◽  
Acceptor Molecule ◽  
Structural Studies ◽  
Halide Anion ◽  
Donor Acceptor ◽  
Halide Salts ◽  
Structure Discussion ◽  
Acceptor Molecules

Two donor/acceptor complexes between halide anion donors and the tetraiodothiophene acceptor with tetra(n-butyl)ammonium countercations, {(H9C4)4N⊕X⊖···(IC)4Sg (X⊖ = I⊖, SCN⊖) could be crystallized from acetone solutions of the components R4N⊕X$ and (IC)4S by using low-gradient techniques. Low temperature structural studies revealed that the molecule packing motifs are layers of halide anion/tetraiodothiophene patterns penetrated each by one of the four R4N⊕ n-butyl chains. The structure discussion emphasizes observed regularities such as the preferred coordination X⊖···I by the polyiodo acceptor molecules to dimers, followed by the additional aggregation to layers and the inclusion of one n-butyl chain fromeach voluminous R4N⊕ countercation. Especially this effect could be an essential crystallization principle for the fascinating self-assembly comprising a halide anion and a polyiodo acceptor molecule.

Wechselwirkungen in Molekülkristallen, 181 [1, 2]. σ-Donator/Akzeptor-Komplexe {MAI4···X⊖ } (X⊖ = Br⊖ , I⊖ , SCN⊖ ) der Tetraiod-Akzeptormoleküle MAI4 (MA = Ethen, Thiophen, N-Methylpyrrol) in Tetraphenylphosphoniumhalogenid-Salzen Interaction in Molecular Crystals, 181 [1, 2]. σ-Donor/Acceptor Complexes {MAI4···X⊖ }(X⊖ = Br⊖, I⊖, SCN⊖ of Tetraiodo Acceptor Molecules MAI4 (MA = Ethene, Thiophene, N-Methylpyrrole) in Tetraphenylphosphonium Halide Salts

2002 ◽  
Vol 57 (8) ◽  
pp. 843-858 ◽  
Keyword(s):  
Low Temperature ◽  
Complex Molecule ◽  
Molecular Crystals ◽  
Ammonium Cation ◽  
The Self ◽  
Acceptor Complex ◽  
Donor Acceptor ◽  
Halide Salts ◽  
Self Aggregation ◽  
Acceptor Molecules

Four donor/acceptor complex phosphoniumhalide salts [(H6C5)4P⊕{X⊖···I4MA}] have been crystallized from chloroform solutions of the components (H6C5)4P⊕X⊖ (X⊖ =Br⊖, I⊖, SCN⊖) and the acceptor molecules MAI4 tetraiodoethene, -thiophene, as well as -N-methylpyrrole by using low-gradient techniques and their low-temperature structures determined. The discussion includes analogous salts with the more flexible tetra(n-butyl)ammonium cation and centers on Br$ coordination to tetraiodothiophene, dimer {X⊖···(IC)4NR}2 disordering in the two tetraiodopyrrole salt, the band structures as well as the donor/acceptor complexes formed with bidentate SCN⊖ anions. The regularities detected in the rather complex molecule packing features add essential aspects to the self-aggregation of polyiodo acceptor molecules and electron- rich donor anions in halide salts with rigid tetraphenylphosphonium and more flexible tetra(n-butyl)ammonium cations.

Crystal structures of four δ-keto esters and a Cambridge Structural Database analysis of cyano–halogen interactions

2015 ◽  
Vol 71 (10) ◽  
pp. 921-928 ◽  
Author(s):  
Kulsoom Kamal ◽  
Hardesh K. Maurya ◽  
Atul Gupta ◽  
Prema G. Vasudev
Keyword(s):  
Crystal Structures ◽  
Crystal Packing ◽  
Noncovalent Interactions ◽  
Halogen Bonding ◽  
Cambridge Structural Database ◽  
Database Analysis ◽  
Molecular Conformations ◽  
Keto Esters ◽  
Organic Molecular Crystals ◽  
Structural Database

The revived interest in halogen bonding as a tool in pharmaceutical cocrystals and drug design has indicated that cyano–halogen interactions could play an important role. The crystal structures of four closely related δ-keto esters, which differ only in the substitution at a single C atom (by H, OMe, Cl and Br), are compared, namely ethyl 2-cyano-5-oxo-5-phenyl-3-(piperidin-1-yl)pent-2-enoate, C19H22N2O3, (1), ethyl 2-cyano-5-(4-methoxyphenyl)-5-oxo-3-(piperidin-1-yl)pent-2-enoate, C20H24N2O4, (2), ethyl 5-(4-chlorophenyl)-2-cyano-5-oxo-3-(piperidin-1-yl)pent-2-enoate, C19H21ClN2O3, (3), and the previously published ethyl 5-(4-bromophenyl)-2-cyano-5-oxo-3-(piperidin-1-yl)pent-2-enoate, C19H21BrN2O3, (4) [Maurya, Vasudev & Gupta (2013).RSC Adv.3, 12955–12962]. The molecular conformations are very similar, while there are differences in the molecular assemblies. Intermolecular C—H...O hydrogen bonds are found to be the primary interactions in the crystal packing and are present in all four structures. The halogenated derivatives have additional aromatic–aromatic interactions and cyano–halogen interactions, further stabilizing the molecular packing. A database analysis of cyano–halogen interactions using the Cambridge Structural Database [CSD; Groom & Allen (2014).Angew. Chem. Int. Ed.53, 662–671] revealed that about 13% of the organic molecular crystals containing both cyano and halogen groups have cyano–halogen interactions in their packing. Three geometric parameters for the C—X...N[triple-bond]C interaction (X = F, Cl, Br or I),viz.the N...Xdistance and the C—X...N and C—N...Xangles, were analysed. The results indicate that all the short cyano–halogen contacts in the CSD can be classified as halogen bonds, which are directional noncovalent interactions.

scholarly journals SYNTHESIS AND STRUCTURE OF 3,5-DIAMINO-1,2,4-TRIAZOLIUM TETRACHLORO-GALLATE

2019 ◽  
Vol 62 (4) ◽  
pp. 121-127
Author(s):  
Tatyana V. Kudayarova ◽  
Elena A. Danilova ◽  
Yuliya A. Piteva ◽  
Kristina E. Mochalina ◽  
Maxim V. Dmitriev
Keyword(s):  
Complex Compound ◽  
Crystal Packing ◽  
Intermolecular Hydrogen Bond ◽  
Cambridge Structural Database ◽  
X Ray Diffraction ◽  
Centrosymmetric Dimer ◽  
X Ray ◽  
Preferential Localization ◽  
Structural Database ◽  
Almost All

This paper discusses the synthesis and structure of a complex compound based on 3,5-diamino-1H-1,2,4-triazole (guanazole) with gallium ions, formed by the interaction of anhydrous gallium (III) chloride and guanazole in dried methanol. After distilling off the solvent under vacuum, the resulting product was washed with hexane, acetone. The target compound was extracted with acetonitrile, and slow evaporation of the latter at room temperature for three days resulted in beige-colored crystals, which were characterized by IR spectroscopy, elemental analysis, mass-spectrometry and X-ray diffraction analysis. The complex composition of gallate, C2H6N5+∙[GaCl4], exists as two crystallographically independent cations and two anions. The complex compound crystallizes in the centrosymmetric space group of the monoclinic syngony. The tetrachlorogallate anion is a slightly distorted tetrahedron, which is typical of structures of this type. 1,2,4-triazolium cations are selectively protonated on the N4 and N4A atoms, however, the site of the preferential localization of the positive charge is the N2 and N2A atoms. In addition to the electrostatic interaction of oppositely charged ions, a developed system of hydrogen bonds plays an important role in the stabilization of the crystal packing: almost all hydrogen and chlorine atoms are involved in its formation. Each of the crystallographically independent cations forms a centrosymmetric dimer due to the intermolecular hydrogen bond N2 – H2···N3 and N2A – H2A···N3A.  A full set of X-ray data is deposited into the Cambridge Structural Database of Compounds - the Cambridge Structural Database (Contributor CCDC 1894815) and it can be gotten from the site www.ccdc.cam.ac.uk/data_request/cif.

The nature of the C–Br⋯Br–C intermolecular interactions found in molecular crystals: a general theoretical-database study

CrystEngComm ◽  
2015 ◽  
Vol 17 (17) ◽  
pp. 3354-3365 ◽  
Author(s):  
Marçal Capdevila-Cortada ◽  
Juan J. Novoa
Keyword(s):  
Intermolecular Interactions ◽  
Theoretical Calculations ◽  
Molecular Crystals ◽  
Cambridge Structural Database ◽  
Database Study ◽  
Structural Database

The properties of C–Br⋯Br–C interactions have been determined by doing MP2 theoretical calculations on model dimers and on dimers taken from the Cambridge Structural Database (presenting Br⋯Br distances within the 3.0 to 4.5 Å range).

Graph-set and packing analysis of hydrogen-bonded networks in polyamide structures in the Cambridge Structural Database

2000 ◽  
Vol 56 (5) ◽  
pp. 857-871 ◽  
Author(s):  
W. D. Samuel Motherwell ◽  
Gregory P. Shields ◽  
Frank H. Allen
Keyword(s):  
Crystal Packing ◽  
Three Dimensional ◽  
Cambridge Structural Database ◽  
Dimensional Network ◽  
Hydrogen Bond Networks ◽  
Structural Database ◽  
Graph Set ◽  
Graph Set Analysis ◽  
Packing Analysis ◽  
Hydrogen Bonded

The hydrogen-bond networks and crystal packing of 81 unique secondary di- and polyamides in the Cambridge Structural Database are investigated. Graph-set analysis, as implemented in the RPluto program, is used to classify network motifs. These have been rationalized in terms of the relative dispositions of the amide groups. Peptide and retropeptides exhibit significant conformational flexibility, which permits alternative hydrogen-bonding patterns. In peptides, dihedral angles of −ψ ≃ φ ≃ 105° allow an antiparallel ladder arrangement, containing rings of either the same or alternating sizes. For retropeptides, and diamides with an odd number of CH2 spacers, this conformation leads to a parallel ladder with rings of equal size. If φ approaches −60° and ψ 180°, ladders adopt a helical twist, and if the conformation is distorted further, a three-dimensional network is usually adopted. Diamides with aromatic or an even number of CH2 spacers generally form either antiparallel ladders or sheets, although some exhibit both polymorphs. Symmetry relationships within and between hydrogen-bonded chains, ladders and sheets in the crystal packing have also been analysed. Polyamides form considerably more complex networks, although many of the structural motifs present in the diamides occur as components of these networks.

The shortest chalcogen...halogen contacts in molecular crystals

2019 ◽  
Vol 75 (5) ◽  
pp. 865-869 ◽  
Author(s):  
Michał Kaźmierczak ◽  
Andrzej Katrusiak
Keyword(s):  
Interatomic Distance ◽  
Main Type ◽  
Van Der Waals ◽  
Molecular Crystals ◽  
Structural Models ◽  
Covalent Bond ◽  
Cambridge Structural Database ◽  
Molecular Arrangement ◽  
Structural Database ◽  
Van Der Waals Radii

The survey of the shortest contacts in structures deposited in the Cambridge Structural Database shows that chalcogen...halogen, halogen...halogen and chalcogen...chalcogen interactions can compete as cohesion forces in molecular crystals. The smallest parameter δ (defined as the interatomic distance minus the sum of relevant van der Waals radii) for Ch...X contacts between chalcogens (Ch: S, Se) and halogens (X: F, Cl, Br, I) is present only in 0.86% out of 30 766 deposited structures containing these atoms. Thus, in less than 1% of these structures can the Ch...X forces be considered as the main type of cohesion forces responsible for the molecular arrangement. Among the 263 structures with the shortest Ch...X contact, there are four crystals where no contacts shorter than the sums of van der Waals radii are present (so-called loose crystals). The smallest δ criterion has been used for distinguishing between the bonding (covalent bond) and non-bonding contacts and for validating the structural models of crystals.

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