共查询到20条相似文献,搜索用时 30 毫秒
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Christopher S. Frampton David D. MacNicol Derek R. Wilson 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(5):o188-o191
The title compounds, C18H21NO and C18H21NS, in their enantiomerically pure forms are isostructural with the enantiomerically pure 4‐(4‐hydroxyphenyl)‐2,2,4‐trimethylchroman and 4‐(2,4‐dihydroxyphenyl)‐2,2,4‐trimethylchroman analogues and form extended linear chains via N—H...O or N—H...S hydrogen bonding along the [100] direction. The absolute configuration for both compounds was determined by anomalous dispersion methods with reference to both the Flack parameter and, for the light‐atom compound, Bayesian statistics on Bijvoet differences. 相似文献
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Nalivela Venu Peddy Vishweshwar Thaimattam Ram Devarakonda Surya Bhattacharya Apurba 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(5):o306-o308
The title compound, C8H17NO2, exists as a zwitterion, adopting a propeller conformation. Molecules self‐assemble to form a hydrogen‐bonded layer parallel to the ab crystallographic plane connected by N+—H...O− and C—H...O− hydrogen bonds. These layers are stacked along the c axis and are stabilized by van der Waals interactions. 相似文献
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Ashokkumar Subashini Kandasamy Ramamurthi Helen Stoeckli‐Evans 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(10):o408-o412
The 4‐chloro‐ [C14H11ClN2O2, (I)], 4‐bromo‐ [C14H10BrN2O2, (II)] and 4‐diethylamino‐ [C18H21N3O2, (III)] derivatives of benzylidene‐4‐hydroxybenzohydrazide, all crystallize in the same space group (P21/c), (I) and (II) also being isomorphous. In all three compounds, the conformation about the C=N bond is E. The molecules of (I) and (II) are relatively planar, with dihedral angles between the two benzene rings of 5.75 (12) and 9.81 (17)°, respectively. In (III), however, the same angle is 77.27 (9)°. In the crystal structures of (I) and (II), two‐dimensional slab‐like networks extending in the a and c directions are formed via N—H...O and O—H...O hydrogen bonds. The molecules stack head‐to‐tail viaπ–π interactions involving the aromatic rings [centroid–centroid distance = 3.7622 (14) Å in (I) and 3.8021 (19) Å in (II)]. In (III), undulating two‐dimensional networks extending in the b and c directions are formed via N—H...O and O—H...O hydrogen bonds. The molecules stack head‐to‐head viaπ–π interactions involving inversion‐related benzene rings [centroid–centroid distances = 3.6977 (12) and 3.8368 (11) Å]. 相似文献
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Alberto Insuasty Braulio Insuasty Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(1):74-76
The molecules of the title compound, C17H21N3OS, are characterized by a wide C—C—C angle at the methine C atom linking the aryl and thiazolidine rings, associated with a short repulsive intramolecular S...H contact between atoms in these two rings. A single piperidine–arene C—H...π hydrogen bond links pairs of molecules into centrosymmetric dimers. 相似文献
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Inside Cover: New Chiral Reagent for Installation of Pharmacophoric (S)‐ or (R)‐2‐(Alkoxyphosphono)‐1‐amino‐2,2‐difluoroethyl Groups (Chem. Eur. J. 21/2016) 下载免费PDF全文
Chen Xie Lijun Zhang Dr. Haibo Mei Dr. Romana Pajkert Dr. Maksym Ponomarenko Dr. Yi Pan Prof. Dr. Gerd‐Volker Röschenthaler Prof. Dr. Vadim A. Soloshonok Dr. Jianlin Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(21):6990-6990
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《Electroanalysis》2006,18(4):417-422
In dimethylformamide containing tetramethylammonium tetrafluoroborate, cyclic voltammograms for reduction of 4,4′‐(2,2,2‐trichloroethane‐1,1‐diyl)bis(chlorobenzene) (DDT) at a glassy carbon cathode exhibit five waves, whereas three waves are observed for the reduction of 4,4′‐(2,2‐dichloroethane‐1,1‐diyl)bis(chlorobenzene) (DDD). Bulk electrolyses of DDT and DDD afford 4,4′‐(ethene‐1,1‐diyl)bis(chlorobenzene) (DDNU) as principal product (67–94%), together with 4,4′‐(2‐chloroethene‐1,1‐diyl)bis(chlorobenzene) (DDMU), 1‐chloro‐4‐styrylbenzene, and traces of both 1,1‐diphenylethane and 4,4′‐(ethane‐1,1‐diyl)bis(chlorobenzene) (DDO). For electrolyses of DDT and DDD, the coulometric n values are essentially 4 and 2, respectively. When DDT is reduced in the presence of a large excess of D2O, the resulting DDNU and DDMU are almost fully deuterated, indicating that reductive cleavage of the carbon–chlorine bonds of DDT is a two‐electron process that involves carbanion intermediates. A mechanistic scheme is proposed to account for the formation of the various products. 相似文献
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Xiao‐Wen Li Yan‐Tuan Li Zhi‐Yong Wu Fu‐Bin Jiang 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(8):m218-m221
The title complex, [Cu4(C11H10N3O4)2(C6H6N4S2)2](C6H2N3O7)2, consists of a circular tetracopper(II) cation with an embedded inversion centre and two uncoordinated picrate (2,4,6‐trinitrophenolate) anions. The CuII cations at the inner sites of N‐(2‐aminoethyl)‐N′‐(2‐carboxylatophenyl)oxamidate(3−) (oxbe) have square‐planar environments and those at the outer sites are in square‐pyramidal geometries. The separations of pairs of CuII cations bridged by cis‐oxamide and carboxylate groups are 5.2217 (5) and 5.2871 (5) Å, respectively. The tetracopper(II) cations and picrate anions are connected by N—H...O hydrogen bonds into a two‐dimensional network parallel to the (010) plane, and these two‐dimensional networks are assembled by two types of π–π stacking interactions into a three‐dimensional supramolecular structure. 相似文献
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Jorge Angulo Cornejo Ketty Ayala Rainer Richter Heinz Bhlig Lothar Hennig Lothar Beyer 《无机化学与普通化学杂志》2005,631(15):3040-3045
Hydrogen Bonds in 1,1‐Bis(2‐hydroxyethyl)‐3‐benzoylthiourea and its Nickel(II)‐ and Copper(II)‐Chelate Complexes The ligand 1,1‐bis(2‐hydroxyethyl)‐3‐benzoylthiourea HL, ( 1 ), yields with nickel(II) and copper(II) ions neutral complexes [NiL2], ( 2 ), and [CuL2], ( 3 ). By X‐ray structure analysis and IR spectroscopy different intramolecular hydrogen bonds (OH…O) and (OH…N) could be identified in both equally coordinated ligands of the [NiL2] molecule. For comparison X‐ray and IR data were also estimated for 1 and 3 . 相似文献
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Li‐Fang Jiang 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(12):m375-m378
In the two title copper(II) complexes, [CuL(C5H7O2)]n, (I), and [CuL′(C5H7O2)], (II), respectively, where HL is 4‐hydroxy‐3‐methoxybenzaldehyde picoloylhydrazone, C14H12N3O3, and HL′ is 4‐methoxybenzaldehyde picoloylhydrazone, C14H12N3O2, the CuII ions display a highly Jahn–Teller‐distorted octahedral and a square‐planar coordination geometry, respectively. In complex (I), two neighbouring CuII atoms are bridged by L− and acetylacetonate, alternately, giving rise to a one‐dimensional chain of CuN2O4 octahedra interconnected by these two ligands along the a axis. In addition, the hydroxy H atom of the vanillin group connects to the carboxyl O atom of the adjacent chain via an O—H...O hydrogen bond, giving rise to a three‐dimensional supramolecular assembly. Complex (II) displays a discrete structure. 相似文献
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Paul V. Bernhardt Brendan P. Macpherson 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):m533-m536
The crystal structures of a pair of closely related macrocyclic cyano‐ and hydroxopentaaminecobalt(III) complexes, as their perchlorate salts, are reported. Although the two complexes, [Co(CN)(C11H27N5)](ClO4)2·H2O and [Co(OH)(C11H27N5)](ClO4)2, exhibit similar conformations, significant differences in the Co—N bond lengths arise from the influence of the sixth ligand (cyano as opposed to hydroxo). The ensuing hydrogen‐bonding patterns are also distinctly different. Disorder in the perchlorate anions was clearly resolved and this was rationalized on the basis of distinct hydrogen‐bonding motifs involving the anion O atoms and the N—H and O—H donors. 相似文献
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Wei‐Wei Fu Man‐Sheng Chen Yang Liu Fu‐Xing Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(4):384-387
The title compound, (C6H9N2S)[ZnCl3{SC(NH2)2}], exists as a zincate where the zinc(II) centre is coordinated by three chloride ligands and a thiourea ligand to form the anion. The organic cation adopts the protonated 4,6‐dimethyl‐2‐sulfanylidenepyrimidin‐1‐ium (L) form of 4,6‐dimethylpyrimidine‐2(1H)‐thione. Two short N—H...Cl hydrogen bonds involving the pyrimidine H atoms and the [ZnCl3L]− anion form a crystallographically centrosymmetric dimeric unit consisting of two anions and two cations. The packing structure is completed by longer‐range hydrogen bonds donated by the thiourea NH2 groups to chloride ligand hydrogen‐bond acceptors. 相似文献