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1.
John Nicolson Low Justo Cobo Braulio Insuasty Henry Insuasty Manuel Nogueras Adolfo Snchez 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o103-o105
In both title compounds, i.e. 3‐methyl‐1,5‐diphenyl‐1,6,7,8‐tetrahydropyrazolo[3,4‐b][1,4]diazepine, C19H18N4, (I), and 5‐(4‐chlorophenyl)‐3‐methyl‐1‐phenyl‐1,6,7,8‐tetrahydropyrazolo[3,4‐b][1,4]diazepine, C19H17ClN4, (II), an N—H?N hydrogen bond links six molecules to form an R(30) ring. Compound (I) crystallizes in the R space group and (II) crystallizes in P with three molecules in the asymmetric unit. The molecule of (I) contains a disordered seven‐membered ring. 相似文献
2.
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
3.
Paul G. Jene Christopher G. Pernin James A. Ibers 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):730-734
The X‐ray structure of 1,2,4,5‐tetrahydroxybenzene (benzene‐1,2,4,5‐tetrol) monohydrate, C6H6O4·H2O, (I), reveals columns of 1,2,4,5‐tetrahydroxybenzene parallel to the b axis that are separated by 3.364 (12) and 3.453 (11) Å. Molecules in adjacent columns are tilted relative to each other by 27.78 (8)°. Water molecules fill the channels between the columns and are involved in hydrogen‐bonding interactions with the 1,2,4,5‐tetrahydroxybenzene molecules. The crystal structure of the adduct 1,2,4,5‐tetrahydroxybenzene–2,5‐dihydroxy‐1,4‐benzoquinone (1/1), C6H6O4·C6H4O4, (II), reveals alternating molecules of 1,2,4,5‐tetrahydroxybenzene and 2,5‐dihydroxy‐1,4‐benzoquinone (both lying on inversion centers), and a zigzag hydrogen‐bonded network connecting molecules in three dimensions. For compound (II), the conventional X‐ray determination, (IIa), is in very good agreement with the synchrotron X‐ray determination, (IIb). When differences in data collection temperatures are taken into account, even the displacement parameters are in very good agreement. 相似文献
4.
Guo‐Wu Rao Wei‐Xiao Hu 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(5):o281-o282
The title compound, C22H24N4O4, was prepared from propyl chloroformate and 3,6‐diphenyl‐1,2‐dihydro‐s‐tetrazine. This reaction yields the title compound rather than dipropyl 3,6‐diphenyl‐1,4‐dihydro‐s‐tetrazine‐1,4‐dicarboxylate. The 2,3‐diazabutadiene group in the central six‐membered ring is not planar; the C=N double‐bond length is 1.285 (2) Å, and the average N—N single‐bond length is 1.401 (3) Å, indicating a lack of conjugation. The ring has a twist conformation, in which adjacent N atoms lie 0.3268 (17) Å from the plane of the ring. The molecule has twofold crystallographic symmetry. 相似文献
5.
Hans‐Georg Weinig Ulrich Koert Burkhard Ziemer 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):e218-e218
The title compound, 2,3‐dimethoxy‐2,3‐dimethyl‐5,6,7,8‐tetrahydro‐4‐oxachroman, C12H22O4, was synthesized as a model compound for substituted diequatorial fixed vicinal trans‐cyclohexanediols. 相似文献
6.
Graeme J. Gainsford Cornelis Lensink Joanne B. Hart Andrew Falshaw 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1396-1398
The title compound, 3,4,5,6‐tetramethoxycyclohexane‐1,2‐diyldioxybis(methyldiphenylphosphonium) diiodide, C36H44O6P22+·2I?, was prepared from a New Zealand natural product, d ‐chiro‐inositol, in order to develop new catalytic metal complexes. The inositol ring retains its usual chair conformation with only minor perturbations caused by the bound diphenylmethylphosphines. Crystal‐packing forces are provided by C—H?I cation–anion interactions. 相似文献
7.
Viktor A. Tafeenko Olga V. Kaukova Rene Peschar Aleksandr V. Petrov Leonid A. Aslanov 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(10):m421-m423
The crystal structure of the title potassium salt, K+·C8HN4O2−, of the organic anion 3‐cyano‐4‐(dicyanomethylene)‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olate shows that the dicyanomethylene moiety is able to accept an electron in the same way as does tetracyanoethylene, to yield the novel product. The organic anion is nearly planar, with deviations caused by steric crowding among the exocyclic cyano groups. The K+ cations lie within tricapped trigonal prisms that stack to form channels. The three‐dimensional structure is completed by the formation of hydrogen‐bonded chains by the anions. 相似文献
8.
Nada Kouti‐Hulita Aleksandar Danilovski Miroslav Maleevi Marina Orei Miljenko Dumi 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1144-1145
The 2,8‐dihydroxy‐1,3,7,9‐tetramethyl‐6,12‐dihydrodipyrido[1,2‐a:1′,2′‐d]pyrazinediylium dication possesses 2/m symmetry and lies in the mirror plane together with a chloride anion and the water O atom. The dication also lies on an inversion centre, i.e. C16H20N2O22+·2Cl?·2H2O. Due to these symmetry constrictions the dication adopts an unexpected planar conformation. Molecules are linked by O—H?O and O—H?Cl hydrogen bonds to form chains, which are cross‐connected by C—H?Cl attractive interactions forming a complex three‐dimensional hydrogen‐bond network. 相似文献
9.
Margarita Ortiz‐Marciales Melvin De Jesús Eduvigis Gonzlez Raphael G. Raptis Peter Baran 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(3):o173-o175
The reaction of (S)‐α,α‐diphenylprolinol with an excess of borane–tetrahydrofuran complex yields a stable crystalline material with the composition C34H38B2N2O2, which features a borane adduct of a spirocyclic structure with two oxazaborolidine rings joined by a central tetrahedral B atom. This dimeric oxazaborolidine complex, viz. 3,3,3′,3′‐tetraphenyl‐1,1′‐spirobi(3a,4,5,6‐tetrahydro‐3H‐pyrrolo[1,2‐c][1,3,2]oxazaborole)–7‐borane, is the dominant product under various reaction conditions; its crystal structure is consistent with 11B, 1H and 13C NMR and IR analyses. 相似文献
10.
Gang Xue Qi Fang Wentao Yu 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(11):o653-o655
4,5‐Propylenedithio‐1,3‐dithiole‐2‐thione, C6H6S5, (I), crystallizes in the centrosymmetric space group P21/c. The molecular packing is characterized by pairs of S⋯S intermolecular contacts between neighbouring molecules, which may account for the rather high thermal stablity of the crystal. 4,5‐Propylenedithio‐1,3‐dithiol‐2‐one, C6H6OS4, (II), in which an O atom replaces the terminal S atom of (I), crystallizes in the non‐centrosymmetric polar space group Cc. The packing pattern of (II) indicates that the macropolarization direction is along [101]. Although the packing patterns are qualitatively significantly different, the molecular structures of (I) and (II) are similar, each exhibiting a chair conformation. 相似文献
11.
Masood Parvez Sumaira Umbreen Farzana Latif Ansari 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):o298-o301
In the structures of 2‐(4‐chlorophenyl)‐4‐(2‐hydroxyphenyl)‐2,3‐dihydro‐1,5‐benzothiazepine, C21H16ClNOS, 4‐(2‐hydroxyphenyl)‐2‐(4‐tolyl)‐2,3‐dihydro‐1,5‐benzothiazepine, C22H19NOS, and 4‐(2‐hydroxyphenyl)‐2‐(3‐methoxyphenyl)‐2,3‐dihydro‐1,5‐benzothiazepine, C22H19NO2S, the central seven‐membered heterocyclic rings adopt twist‐boat conformations in which the N atoms are involved in strong intramolecular hydrogen bonds with the hydroxyl H atoms, resulting in six‐membered rings. 相似文献
12.
Il Yoon Byeong Soon Yoo Shim Sung Lee Bong Gon Kim 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):758-759
The preparation and crystal structure of the title compound, cis‐dichloro[6,9‐dioxa‐3,12‐dithiabicyclo[12.4.0]octadeca‐14,‐16,18(1)‐triene‐S,S′]palladium(II), [PdCl2(C14H20O2S2)], are described. The Pd atom has a square‐planar environment, coordinated to two S atoms of the dithiadioxa macrocycle and to two Cl? ions. The non‐coordinating O atoms are oriented away from the metal coordination plane. Upon complexation, a bicyclic chelate structure, which consists of a seven‐ and an eleven‐membered ring, is formed. 相似文献
13.
A. R. Choudhury K. Nagarajan T. N. Guru Row 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(3):o219-o222
The crystal and molecular structures of the three 4‐ketotetrahydroindoles 2‐(4‐chlorophenyl)‐1‐(4‐fluorophenyl)‐6,6‐dimethyl‐4,5,6,7‐tetrahydro‐1H‐indol‐4‐one (C22H19ClFNO), (I), 1‐(4‐fluorophenyl)‐2‐(4‐methoxyphenyl)‐6,6‐dimethyl‐4,5,6,7‐tetrahydro‐1H‐indol‐4‐one (C23H22FNO2), (II), and 6,6‐dimethyl‐1,2‐diphenyl‐4,5,6,7‐tetrahydro‐1H‐indol‐4‐one (C22H21NO), (III), have been determined via single‐crystal X‐ray diffraction in order to study the intermolecular interactions therein. All three structures are stabilized via intermolecular C—H⋯O and C—H⋯π interactions, generating different molecular motifs. 相似文献
14.
Konstantin Karaghiosoff Thomas M. Klaptke Alexej Michailovski Gerhard Holl 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o580-o581
The title compound (systematic name: 4,10‐dinitro‐2,6,8,12‐tetraoxa‐4,10‐diazatetracyclo[5.5.0.03,11.05,9]dodecane), C6H6N4O8, exhibits the highest density among known N‐nitramines, due to its close‐packed crystal structure. It may be regarded as consisting of a distorted hexagonal close‐packed lattice formed by the isowurtzitane cages, with the nitro groups occupying the free space between the cages. 相似文献
15.
Xiang‐Jin Xie Xiang‐Lin Jin Ka‐Luo Tang 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):696-697
In the title compound, tetracarbonyl(4,7‐diphenyl‐1,10‐phenanthroline‐N,N′)molybdenum(0), [Mo(C24H16N2)(CO)4], the Mo‐atom coordination is distorted octahedral, with two CO groups cis to each other, but each trans to an N atom of the 4,7‐diphenyl‐1,10‐phenanthroline (dpphen) ligand, and with the other two CO groups trans to each other and on the axis position. The complex has better solubility than [Mo(phen)(CO)4], where phen is 1,10‐phenanthroline. 相似文献
16.
(Borohydrido)(18‐crown‐6)potassium and (borohydrido)(dibenzo‐18‐crown‐6)(tetrahydrofuran)potassium
Claude Villiers Michel Ephritikhine Pierre Thury 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(7):m275-m277
In the two compounds (borohydrido)(1,4,7,10,13,16‐hexaoxacyclooctadecane‐κ6O)potassium, [K(BH4)(C12H24O6)], (I), and (borohydrido)(1,4,7,10,13,16‐hexaoxa‐2,3:11,12‐dibenzocyclooctadeca‐2,11‐diene‐κ6O)(tetrahydrofuran)potassium, [K(BH4)(C4H8O)(C20H24O6)], (II), the K atom is bound to the six O atoms of the crown ether and to a tridentate borohydride group, with further coordination to a tetrahydrofuran molecule in (II). The alkali metal ion environment is thus distorted hexagonal–pyramidal in (I) and bipyramidal in (II). 相似文献
17.
Antonio C. Doriguetto Marcelo H. Santos Javier A. Ellena Tanus J. Nagem 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1095-1097
The natural compound 5,10‐dihydroxy‐2,2‐dimethylpyrano[3,2‐b]xanthen‐6(2H)‐one (6‐deoxyjacareubin), C18H14O5, was isolated from leaves of Vismia latifolia (Guttiferae family). The compound has four six‐membered rings. The molecule has two planar benzenoid and one planar pyranoid ring, plus a pyranoid ring in a distorted chair conformation. The crystal is stabilized by one intra‐ and one intermolecular hydrogen bond. 相似文献
18.
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
19.
Pierre Morel Paul Schaffer James F. Britten John F. Valliant 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):m601-m604
The title compounds, bis[1,2‐dicarba‐closo‐dodecaboran(12)‐1‐yl]mercury(II) dichloromethane solvate, [Hg(C2B10H11)2]·CH2Cl2, (I), and bis[1,12‐dicarba‐closo‐dodecaboran(12)‐1‐yl]mercury(II) tetrahydrofuran solvate, [Hg(C2B10H11)2]·C4H8O, (II), were prepared in excellent yields using a robust synthetic procedure involving the reaction of HgCl2 with the appropriate monolithiocarborane. X‐Ray analysis of the products revealed strong interactions between the Hg atoms in both complexes and the respective lattice solvent. The distances between the HgII centers and the Cl atoms of the dichloromethane solvent molecule in the ortho‐carborane derivative, (I), and the O atom of the tetrahydrofuran molecule in the para‐carborane complex, (II), are shorter than the sums of the van der Waals radii for Hg and Cl (3.53 Å), and Hg and O (3.13 Å), respectively, indicating moderately strong interactions. There are two crystallographically independent molecules in the asymmetric unit of both compounds, which, in each case, are related by differing relative positions of the cages. 相似文献
20.
Michael Bolte Karl Hensen Alexander Faber 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):e499-e500
The reactions of GeBr4 with 4‐methylpyridine and 3,4‐dimethylpyridine lead to tetrabromobis(4‐methylpyridine)germanium, [GeBr4(C6H7N)2], and tetrabromobis(3,4‐dimethylpyridine)germanium, [GeBr4(C7H9N)2], respectively. These structures show the same features as the corresponding silicon complexes. 相似文献