共查询到20条相似文献,搜索用时 328 毫秒
1.
Maurice Abou Rida Joseph Saikaili Anthony K. Smith Alain Thozet 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):352-353
The title compound, dicarbonyl‐1κ2C‐di‐μ‐chloro‐1:2κ4Cl‐[cis,cis‐2(η4)‐1,5‐cyclooctadiene]dirhodium(I), [Rh2Cl2(C8H12)(CO)2], consists of a dichloro‐bridged dimer of rhodium, with a non‐bonded Rh?Rh distance of 3.284 (2) Å. One Rh atom is coordinated to two carbonyl ligands, while the other Rh atom is coordinated to the cyclooctadiene moiety. 相似文献
2.
David J. Wiedenfeld Vladimir N. Nesterov Mark A. Minton Crystal L. Montoya 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):o536-o538
The title compounds, 1‐chloro‐3,6‐dimethoxy‐2,5‐dimethylbenzene, (IIIa), and 1‐chloro‐3,6‐dimethoxy‐2,4‐dimethylbenzene, (IIIb), both C10H13ClO2, were obtained from 2,5‐ and 2,6‐dimethyl‐1,4‐benzoquinone, respectively, and are intermediates in the synthesis of ammonium quinone derivatives. The isomers have different substituents around the methoxy groups and crystallize in different space groups. In both molecules, the methoxy groups each have different orientations with respect to the benzene ring. In both cases, one methoxy group lies in the plane of the ring and can participate in conjugation with the aromatic system, while the second is almost perpendicular to the plane of the aromatic ring. The C—O—C bond angles around these substituents are also different: 117.5 (4) and 118.2 (3)° in (IIIa) and (IIIb), respectively, when the methoxy groups lie in the plane of the ring, and 114.7 (3) and 113.6 (3)° in (IIIa) and (IIIb), respectively, when they are out of the plane of the ring. 相似文献
3.
Takashiro Akitsu Yuiri Takeuchi Yasuaki Einaga 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):o801-o802
The title compound, (RS)‐3,5‐dichloro‐2‐{[(1‐phenylethyl)imino]methyl}phenol, C15H13Cl2NO, was synthesized from racemic 1‐phenylethylamine and 3,5‐dichlorosalicylaldehyde. The π‐conjugate system around the imine group is essentially planar in the phenol–imine tautomer. Intramolecular O⋯N hydrogen‐bond and intermolecular C—H⋯π interactions are present in the crystal structure. 相似文献
4.
Guangrong Zheng Sean Parkin Linda P. Dwoskin Peter A. Crooks 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o9-o11
The crystal structures of the title compounds, 2α,4α‐dibenzyl‐3α‐tropanol (2α,4α‐dibenzyl‐8‐methyl‐8‐azabicyclo[3.2.1]octan‐3α‐ol), C22H27NO, (I), and 2α,4α‐dibenzyl‐3β‐tropanol (2α,4α‐dibenzyl‐8‐methyl‐8‐azabicyclo[3.2.1]octan‐3β‐ol), C22H27NO, (II), show that both compounds have a piperidine ring in a chair conformation and a pyrrolidine ring in an envelope conformation. Isomer (I) is asymmetric, the benzyl groups having different orientations, whereas isomer (II) is mirror symmetric, and the N and O atoms, the C atom attached to the hydroxy group, and the methyl C atom attached to the N atom lie on the mirror plane. In the crystal structures of both (I) and (II), the molecules are linked together by intermolecular O—H⋯N hydrogen bonds to form chains that run parallel to the a direction in (I) and parallel to b in (II). 相似文献
5.
David J. Wiedenfeld Vladimir N. Nesterov Mark A. Minton David R. Glass 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):o700-o702
Bis(2,5‐dimethoxy‐4‐methylphenyl)methane, C19H24O4, (IIa), was obtained and characterized as a minor product from the reaction of toluhydroquinone dimethyl ether (1,4‐dimethoxy‐2‐methylbenzene) with N‐(hydroxymethyl)trifluoroacetamide. Similarly, bis(2,5‐dimethoxy‐3,4,6‐trimethylphenyl)methane, C23H32O4, (IIb), was prepared from the corresponding reaction of trimethylhydroquinone dimethyl ether (2,5‐dimethoxy‐1,3,4‐trimethylbenzene). The molecules of (IIa) and (IIb) each lie on a twofold axis passing through the methylene group. The dihedral angle between the planar phenyl rings is 73.4 (1)° in (IIa) and 77.9 (1)° in (IIb). The external bond angles around the bridging methylene group are 116.6 (2) and 117.3 (2)° for (IIa) and (IIb), respectively. In (IIa), the methoxy substituents lie in the plane of the ring and are conjugated with the aromatic system, whereas in (IIb), they are almost perpendicular to the phenyl ring and are positioned on opposite sides. 相似文献
6.
Natalya Fridman Moshe Kapon Menahem Kaftory 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):o685-o686
The molecules of 2‐chloro‐4,6‐dimethoxy‐1,3,5‐triazine, C5H6ClN3O2, lie on a crystallographic mirror plane. There is a close contact of 3.180 (3) Å between one of the methyl C atoms and the N atom of a neighboring molecule. Differential scanning calorimetry measurements show that methyl rearrangement does not take place in the solid state, despite the close proximity of the methyl group to the N atom. 相似文献
7.
Sylvain Berns Martha I. Berros Cecilia Rodríguez de Barbarín Francisco Snchez‐Viesca 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o151-o153
In the title compounds, 2‐amino‐4‐(2‐chloro‐4,5‐dimethoxyphenyl)‐1,3‐thiazole, C11H11ClN2O2S, (I), and 4‐(2‐chloro‐4,5‐dimethoxyphenyl)‐2‐methyl‐1,3‐thiazole, C12H12ClNO2S, (II), the dihedral angles between the thiazole moiety and the chloroaryl group are 51.61 (10) and 8.44 (14)°, respectively. This difference is a consequence of intermolecular hydrogen bonds forcing the stabilization of a twisted rotamer in (I). Substitution of the amino function by a methyl group precludes these contacts, giving a flat rotamer in (II). 相似文献
8.
Anthony Linden A. S. Muhammad Sofian C. Kuan Lee 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):o718-o720
At 160 K, one of the Cl atoms in the furanoid moiety of 3‐O‐acetyl‐1,6‐dichloro‐1,4,6‐trideoxy‐β‐d ‐fructofuranosyl 2,3,6‐tri‐O‐acetyl‐4‐chloro‐4‐deoxy‐α‐d ‐galactopyranoside, C20H27Cl3O11, is disordered over two orientations, which differ by a rotation of about 107° about the parent C—C bond. The conformation of the core of the molecule is very similar to that of 3‐O‐acetyl‐1,4,6‐trichloro‐1,4,6‐trideoxy‐β‐d ‐tagatofuranosyl 2,3,6‐tri‐O‐acetyl‐4‐chloro‐4‐deoxy‐α‐d ‐galactopyranoside, particularly with regard to the conformation about the glycosidic linkage. 相似文献
9.
10.
Anthony Linden Fatemeh Ghorbani‐Salman Pour Roland A. Breitenmoser Heinz Heimgartner 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):634-637
The morpholine ring of the title dione, C13H15NO3, shows a boat conformation that is distorted towards a twist‐boat, with the boat ends being the two Csp3 atoms of the ring. The benzyl substituent is in the favoured `exo' position. In the monothione derivative, (±)‐6‐benzyl‐3,3‐dimethyl‐5‐thioxomorpholin‐2‐one, C13H15NO2S, this ring has a much flatter conformation that is midway between a boat and an envelope, with the dimethyl end being almost planar. The orientation of the benzyl group is `endo'. The dithione derivative, (±)‐6‐benzyl‐3,3‐dimethylmorpholine‐2,5‐dithione, C13H15NOS2, has two symmetry‐independent molecules, which show different puckering of the morpholine ring. One molecule has a flattened envelope conformation distorted towards a screw‐boat, while the conformation in the other molecule is similar to that in the monothione derivative. Intermolecular hydrogen bonds link the molecules in the three compounds, respectively, into centrosymmetric dimers, infinite chains, and dimers made up of one of each of the symmetry‐independent molecules. 相似文献
11.
Paul V. Bernhardt 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):744-746
The title pendent‐arm macrocyclic hexaamine ligand binds stereospecifically in a hexadentate manner, and we report here its isomorphous NiII and ZnII complexes (both as perchlorate salts), namely (cis‐6,13‐dimethyl‐1,4,8,11‐tetraazacyclotetradecane‐6,13‐diamine‐κ6N)nickel(II) diperchlorate, [Ni(C12H30N6)](ClO4)2, and (cis‐6,13‐dimethyl‐1,4,8,11‐tetraaza‐cyclotetradecane‐6,13‐diamine‐κ6N)zinc(II) diperchlorate, [Zn(C12H30N6)](ClO4)2. Distortion of the N—M—N valence angles from their ideal octahedral values becomes more pronounced with increasing metal‐ion size and the present results are compared with other structures of this ligand. 相似文献
12.
Anthony Linden A. S. Muhammad Sofian C. Kuan Lee 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):o711-o714
At 160 K, the glucopyranosyl ring in 1,6‐dichloro‐1,6‐dideoxy‐β‐d ‐fructofuranosyl 4‐chloro‐4‐deoxy‐α‐d ‐glucopyranoside monohydrate, C12H19Cl3O8·H2O, has a near ideal 4C1 chair conformation, while the fructofuranosyl ring has a 4T3 conformation. The conformation of the sugar molecule is quite different to that of sucralose, particularly in the conformation about the glycosidic linkage, which affects the observed pattern of intramolecular hydrogen bonds. A complex series of intermolecular hydrogen bonds links the sugar and water molecules into an infinite three‐dimensional framework. 相似文献
13.
Shyamaprosad Goswami Reshmi Mukherjee Kumaresh Ghosh Ibrahim Abdul Razak S. Shanmuga Sundara Raj Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):716-717
In the title compound, N‐(6‐chloro‐4‐oxo‐3,4‐dihydropteridin‐2‐yl)‐2,2‐dimethylpropanamide, C11H12ClN5O2, the rings in the pterin moiety are planar. The amide carbonyl O atom is in syn‐periplanar conformation while the C—N—C—C propanamide linkage is antiperiplanar. The N—H?N and N—H?O intermolecular hydrogen bonds transform the molecules into infinite chains. 相似文献
14.
Nina Lah Ivan Leban Alenka Majcen‐Le Marchal Philippe Le Grel Albert Robert Joachim Sieler Gerald Giester 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1164-1167
The crystal structures of the first stable α‐diol from the α‐halogenopyruvamide series, 3‐chloro‐2,2‐dihydroxy‐3‐phenylpropanamide, C9H10ClNO3, and three products [3‐(4‐chlorophenyl)‐2‐cyano‐2,3‐epoxypropanamide, C10H7ClN2O2, 3‐bromo‐2‐cyano‐2‐hydroxy‐3‐p‐tolylpropanamide, C11H11BrN2O2, 3‐bromo‐2‐oxo‐3‐p‐tolylpropanamide, C10H10BrNO2] obtained during the systematic synthesis of α‐halogenopyruvamides are reported. The crystal structures are dominated by hydrogen bonds involving an amide group. The stability of the geminal diol could be ascribed to hydrogen bonds which involve both hydroxyl groups. 相似文献
15.
Russell G. Baughman Kenneth L. Martin Rajendra K. Singh James O. Stoffer 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o103-o106
In 2,4‐dihydroxybenzaldehyde 2,4‐dinitrophenylhydrazone N,N‐dimethylformamide solvate {or 4‐[(2,4‐dinitrophenyl)hydrazonomethyl]benzene‐1,3‐diol N,N‐dimethylformamide solvate}, C13H10N4O6·C3H7NO, (X), 2,4‐dihydroxyacetophenone 2,4‐dinitrophenylhydrazone N,N‐dimethylformamide solvate (or 4‐{1‐[(2,4‐dinitrophenyl)hydrazono]ethyl}benzene‐1,3‐diol N,N‐dimethylformamide solvate), C14H12N4O6·C3H7NO, (XI), and 2,4‐dihydroxybenzophenone 2,4‐dinitrophenylhydrazone N,N‐dimethylacetamide solvate (or 4‐{[(2,4‐dinitrophenyl)hydrazono]phenylmethyl}benzene‐1,3‐diol N,N‐dimethylacetamide solvate), C19H14N4O6·C4H9NO, (XII), the molecules all lack a center of symmetry, crystallize in centrosymmetric space groups and have been observed to exhibit non‐linear optical activity. In each case, the hydrazone skeleton is fairly planar, facilitated by the presence of two intramolecular hydrogen bonds and some partial N—N double‐bond character. Each molecule is hydrogen bonded to one solvent molecule. 相似文献
16.
Anthony Linden Agnieszka Majchrzak Jovita Cavegn Grzegorz Mloston Heinz Heimgartner 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o480-o484
The four oligosulfanes, bis(1‐chloro‐2,2,4,4‐tetramethyl‐3‐oxocyclobutan‐1‐yl)disulfane, C16H24Cl2O2S2, (III), 1,3‐bis(1‐chloro‐2,2,4,4‐tetramethyl‐3‐oxocyclobutan‐1‐yl)trisulfane, C16H24Cl2O2S3, (V), 1,4‐bis(1‐chloro‐2,2,4,4‐tetramethyl‐3‐oxocyclobutan‐1‐yl)tetrasulfane, C16H24Cl2O2S4, (VII), and 1,6‐bis(1‐chloro‐2,2,4,4‐tetramethyl‐3‐oxocyclobutan‐1‐yl)hexasulfane, C16H24Cl2O2S6, (VIII), all have similar geometric parameters, with the C—C bond lengths involving the chloro‐substituted cyclobutanyl C atom being elongated to about 1.59 Å. There are two molecules in the asymmetric units of the tri‐ and tetrasulfanes, and the molecules in the latter compound have local C2 symmetry. The molecule of the hexasulfane has crystallographic C2 symmetry. Most of the cyclobutanyl rings are not perfectly planar and have slight but varying degrees of distortion towards a flattened tetrahedron. The polysulfane chain in each structure has a helical conformation, with each additional S atom in the chain adding approximately one quarter of a turn to the helix. 相似文献
17.
Lee J. Higham P. Gabriel Kelly Helge Müller‐Bunz Declan G. Gilheany 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(5):o308-o311
The Ramirez ylide undergoes electrophilic substitution with dialkyl acetylenedicarboxylates, yielding a mixture of the Z and E adducts. The crystal structure analyses of the two adducts formed using dimethylacetylene, viz. dimethyl (E)‐ and (Z)‐1‐[2‐(triphenylphosphoranylidene)cyclopentadien‐1‐yl]ethylenedicarboxylate, both C29H25O4P, explain an unusual chemical shift observed for the vinyl H atom of the Z adduct, which had previously precluded a definitive assignment of the isomers. In addition, the structures explain why only one of the isomers reacts further with acetylene esters to produce azulenes with a rare substitution pattern. 相似文献
18.
Kai Liang Yi‐Zhi Li He‐Gen Zheng Xin‐Quan Xin 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):m310-m312
In the title compound, [1,4‐bis(diphenylphosphino)butane‐2κ2P,P′]di‐μ‐thio‐1:2κ4S‐dithio‐1κ2S‐palladium(II)tungsten(VI) N,N′‐dimethylformamide hemisolvate hemihydrate, [PdWS4(C28H28P2)]·0.5C3H7NO·0.5H2O, the Pd atom is coordinated by two S atoms from the distorted‐tetrahedral [WS4]2− anion and two P atoms from the dppb molecule [dppb is 1,4‐bis(diphenylphosphino)butane] in an approximately square‐planar configuration. A puckered seven‐membered ring is formed by the Pd atom and the dppb ligand. 相似文献
19.
Tullio Pilati Gianluigi Casalone 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o178-o180
The title diastereoisomers, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate and methyl 5‐(S)‐[2‐(R)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate, both C19H23N3O5, have been studied in two crystalline forms. The first form, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate–methyl 5‐(S)‐[2‐(R)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate (1/1), 2(S),5(S)‐C19H23N3O5·2(R),5(S)‐C19H23N3O5, contains both S,S and S,R isomers, while the second, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate, 2(S),5(S)‐C19H23N3O5, is the pure S,S isomer. The S,S isomers in the two structures show very similar geometries, the maximum difference being about 15° on one torsion angle. The differences between the S,S and S,R isomers, apart from those due to the inversion of one chiral centre, are more remarkable, and are partially due to a possible rotational disorder of the 2‐(methoxycarbonyl)tetrahydropyrrole group. 相似文献
20.
Andrzej Gzella Maria D. Rozwadowska 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):981-982
The absolute configuration of the title compound, alternatively called (+)‐(4,5‐dihydro‐2,5‐diphenyloxazol‐4‐yl)methanol, C16H15NO2, has been confirmed as 4S,5S. The hydroxymethyl group and phenyl ring at the asymmetric C atoms exhibit β and α orientations, respectively. The exocyclic C—C bonds at the asymmetric C atoms are mutually anticlinal (?ac). The hydroxyl group and the N atom of the oxazoline ring are involved in an intermolecular hydrogen bond leading to chains of molecules. 相似文献