Unusual Hexacoordination in a Triorganotin Fluoride Supported by Intermolecular Hydrogen Bonds. Crystal and Molecular Structures of 1-Aza-5-stanna-5-halotricyclo[3.3.3.01.5]undecanes N(CH2CH2CH2)3SnF.cntdot.H2O and N(CH2CH2CH2)3SnX (X = Cl, Br, I)

1995 ◽  
Vol 14 (6) ◽  
pp. 2827-2834 ◽  
Author(s):  
Ute Kolb ◽  
Martin Draeger ◽  
Manfred Dargatz ◽  
Klaus Jurkschat
2018 ◽  
Vol 74 (12) ◽  
pp. 1735-1740 ◽  
Author(s):  
James L. Wardell ◽  
Edward R. T. Tiekink

The crystal and molecular structures of the title molecular salts, C4H12NO+·C7H5N2O4 −, (I), C6H16NO+·C7H5N2O4 −, (II), and C4H12NO3 +·C7H5N2O4 −, (III), are described. The common feature of these salts is the presence of the 2-amino-4-nitrobenzoate anion, which exhibit non-chemically significant variations in the conformational relationships between the carboxylate and nitro groups, and between these and the benzene rings they are connected to. The number of ammonium-N—H H atoms in the cations increases from one to three in (I) to (III), respectively, and this variation significantly influences the supramolecular aggregation patterns in the respective crystals. Thus, a linear supramolecular chain along [100] sustained by charge-assisted tertiary-ammonium-N—H...O(carboxylate), hydroxy-O—H...O(carboxylate) and amino-N—H...O(carboxylate) hydrogen-bonds is apparent in the crystal of (I). Chains are connected into a three-dimensional architecture by methyl-C—H...O(hydroxy) and π–π interactions, the latter between benzene rings [inter-centroid separation = 3.5796 (10) Å]. In the crystal of (II), a supramolecular tube propagating along [901] arises as a result of charge-assisted secondary-ammonium-N—H...O(carboxylate) and hydroxy-O—H...O(carboxylate) hydrogen-bonding. These are connected by methylene- and methyl-C—H...O(nitro) and π–π stacking between benzene rings [inter-centroid separation = 3.5226 (10) Å]. Finally, double-layers parallel to (100) sustained by charge-assisted ammonium-N—H...O(carboxylate), ammonium-N—H...O(hydroxy) and hydroxy-O—H...O(carboxylate) hydrogen-bonds are apparent in the crystal of (III). These are connected in a three-dimensional architecture by amine-N—H...O(nitro) hydrogen-bonds.


1983 ◽  
Vol 38 (2) ◽  
pp. 149-154 ◽  
Author(s):  
U. Ensinger ◽  
W. Schwarz ◽  
A. Schmidt

Abstract The crystal and molecular structures of triethylammonium tetrachloroantimonate(III) (1) and tris[methylammonium] hexachloroantimonate(III) (2) were determined by X-ray analysis. In compound 1, SbCl3 molecules are bridged by Cl ions to form chains. The coordination of Sb by Cl atoms yields a distorted tetragonal-pyramidal structure. In compound 2 there are chains of SbCL4- ions, again through bridging by Cl ions. One Cl ion has no contacts to Sb. The cations of 1 and 2 form hydrogen bonds with the anionic components.


Author(s):  
Sang Loon Tan ◽  
Edward R. T. Tiekink

The crystal and molecular structures of the title 1:2 co-crystal, C14H14N4O2·2C7H6O2, are described. The oxalamide molecule has a (+)-antiperiplanar conformation with the 4-pyridyl residues lying to either side of the central, almost planar C2N2O2 chromophore (r.m.s. deviation = 0.0555 Å). The benzoic acid molecules have equivalent, close to planar conformations [C6/CO2 dihedral angle = 6.33 (14) and 3.43 (10)°]. The formation of hydroxy-O—H...N(pyridyl) hydrogen bonds between the benzoic acid molecules and the pyridyl residues of the diamide leads to a three-molecule aggregate. Centrosymmetrically related aggregates assemble into a six-molecule aggregate via amide-N—H...O(amide) hydrogen bonds through a 10-membered {...HNC2O}2 synthon. These are linked into a supramolecular tape via amide-N—H...O(carbonyl) hydrogen bonds and 22-membered {...HOCO...NC4NH}2 synthons. The contacts between tapes to consolidate the three-dimensional architecture are of the type methylene-C—H...O(amide) and pyridyl-C—H...O(carbonyl). These interactions are largely electrostatic in nature. Additional non-covalent contacts are identified from an analysis of the calculated Hirshfeld surfaces.


2017 ◽  
Vol 73 (8) ◽  
pp. 1227-1231
Author(s):  
Li Yee Then ◽  
C. S. Chidan Kumar ◽  
Huey Chong Kwong ◽  
Yip-Foo Win ◽  
Siau Hui Mah ◽  
...  

2-(Benzofuran-2-yl)-2-oxoethyl 2-chlorobenzoate, C17H11ClO4 (I), and 2-(benzofuran-2-yl)-2-oxoethyl 2-methoxybenzoate, C18H14O5 (II), were synthesized under mild conditions. Their chemical and molecular structures were analyzed by spectroscopic and single-crystal X-ray diffraction studies, respectively. These compounds possess different ortho-substituted functional groups on their phenyl rings, thus experiencing extra steric repulsion force within their molecules as the substituent changes from 2-chloro (I) to 2-methoxy (II). The crystal packing of compound (I) depends on weak intermolecular hydrogen bonds and π–π interactions. Molecules are related by inversion into centrosymmetric dimers via C—H...O hydrogen bonds, and further strengthened by π–π interactions between furan rings. Conversely, molecules in compound (II) are linked into alternating dimeric chains propagating along the [101] direction, which develop into a two-dimensional plate through extensive intermolecular hydrogen bonds. These plates are further stabilized by π–π and C—H...π interactions.


2021 ◽  
Author(s):  
Yuliua P. Tupolova ◽  
Sergey I. Levchenkov ◽  
Leonid D Popov ◽  
Vladimir E Lebedev ◽  
Vadim Minin ◽  
...  

Copper(II) coordination compounds with the condensation product of the diacetylmonoxime and 2-hydrazino-4,6-dimethylpirimidine (H2L) with composition [Сu(Н2L)Br2]·Н2О (I) and [Сu(Н2L)Cl2] (II) were synthesized. Molecular structures of the compounds were established with...


2008 ◽  
Vol 64 (3) ◽  
pp. 375-382 ◽  
Author(s):  
Elżbieta Trzop ◽  
Ilona Turowska-Tyrk

Variations in crystal and molecular structures, brought about by the intramolecular [4 + 4] photocycloaddition of bi(anthracene-9,10-dimethylene), were monitored using X-ray diffraction. The cell volume increased by 0.8% until the reaction was ca 40% complete, and afterwards decreased by 1.6% during the remainder of the photoreaction. The changes of the a and b lattice parameters were correlated with the changes of the molecular shape and packing. The distance between the directly reacting C atoms varied in a manner not observed for other photochemical reactions in crystals. It was constant until ca 20% photoreaction progress, then decreased, and later stabilized from ca 40% photoreaction progress. This phenomenon was explained by interplay between stress resulting from the presence of product molecules and the rigidity of reactant molecules. Changes of the orientation of molecules during the photoreaction were smaller than in the case of other monitored photochemical reactions in crystals owing to similarities in the shape and packing of reactant and product molecules. Weak C—H...π hydrogen bonds exist among reactant molecules in the pure reactant and partly reacted crystals.


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