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1.
Andrzej Gzella Urszula Wrzeciono Wolfram Pppel 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1161-1163
The structure analyses of racemic 3‐chloro‐1‐(4‐morpholino‐5‐nitroimidazol‐1‐yl)propan‐2‐ol, C10H15ClN4O4, (II), and 3‐chloro‐1‐(5‐morpholino‐4‐nitroimidazol‐1‐yl)propan‐2‐ol, C10H15ClN4O4, (III), have been undertaken in order to determine the position of the morpholine residue in these two isomers. The morpholine residue in (II) is connected at the 4‐position, while in (III), it is connected at the 5‐position of the imidazole ring. The morpholine mean planes and nitro groups in the two compounds deviate from the imidazole planes to different extents. The nitro groups in (II) and (III) take part in the conjugation system of the imidazole rings. In consequence, the exocyclic C—N bonds are significantly shorter than the normal single Csp2—NO2 bond and the nitro groups in (II) and (III) show an extraordinary stability on treatment with morpholine and piperidine [Gzella, Wrzeciono & Pöppel (1999). Acta Cryst. C 55 , 1562–1565]. In the crystal lattice, the molecules of both compounds are linked by O—H?N and C—H?O intermolecular hydrogen bonds. 相似文献
2.
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
3.
Simon J. Garden Fernanda R. da Cunha James L. Wardell Janet M. S. Skakle John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o463-o466
In 2,6‐diiodo‐4‐nitrophenol, C6H3I2NO3, the molecules are linked, by an O—H?O hydrogen bond and two iodo–nitro interactions, into sheets, which are further linked into a three‐dimensional framework by aromatic π–π‐stacking interactions. The molecules of 2,6‐diiodo‐4‐nitrophenyl acetate, C8H5I2NO4, lie across a mirror plane in space group Pnma, with the acetyl group on the mirror, and they are linked by a single iodo–nitro interaction to form isolated sheets. The molecules of 2,6‐diiodo‐4‐nitroanisole, C7H5I2NO3, are linked into isolated chains by a single two‐centre iodo–nitro interaction. 相似文献
4.
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
5.
Janet M. S. Skakle James L. Wardell Solange M. S. V. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):m413-m417
In the crystal structures of (4‐nitrophenylsulfanylmethyl)triphenylstannane, [Sn(C6H5)3(C7H6NO2S)], (I), and (4‐nitrophenylsulfonylmethyl)triphenylstannane, [Sn(C6H5)3(C7H6NO4S)], (II), the molecules are linked by paired C—H?O hydrogen bonds into centrosymmetric dimers which combine to form sheets. In (I), two such dimers form to give R(10) and R(24) rings. In (II), similar dimers form, here with R(10) and R(18) rings, but with an additional dimer due to the presence of the sulfone group, giving R(10) rings. In both structures, C—H?π interactions lead to a doubling of the width of the sheets. 相似文献
6.
Bartosz Zarychta Anna Piecyk‐Mizgaa Zdzisaw Daszkiewicz Jacek Zaleski 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(8):o515-o517
The structures of the two title isomeric compounds (systematic names: N‐methyl‐N,2‐dinitroaniline and N‐methyl‐N,3‐dinitroaniline, both C7H7N3O4) are slightly different because they exhibit different steric hindrances and hydrogen‐bonding environments. The aromatic rings are planar. The –N(Me)NO2 and –NO2 groups are not coplanar with the rings. Comparison of the geometric parameters of the ortho, meta and para isomers together with those of N‐methyl‐N‐phenylnitramine suggests that the position of the nitro group has a strong influence on the aromatic ring distortion. The crystal packing is stabilized by weak C—H⋯O hydrogen bonds to the nitramine group. 相似文献
7.
Tod J. Miller Yanwen Fu Frank R. Fronczek Robert P. Hammer 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e574-e575
The title compound, C18H19NO4, is the key synthetic intermediate in the preparation of α,α‐dibenzyl‐α‐amino acid (dibenzylglycine, Dbg), the disubstituted homologue of phenylalanine, following the dialkylation of ethyl nitroacetate. The molecule does not have its potential mirror symmetry in the crystal, with the two benzyl groups forming N—C—C—C torsion angles of 60.31 (13) and 79.89 (13)°. 相似文献
8.
Yoriko Sonoda Seiji Tsuzuki Nobuyuki Tamaoki Midori Goto 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):o196-o200
The crystal structures of the four E,Z,E isomers of 1‐(4‐alkoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, namely (E,Z,E)‐1‐(4‐methoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C19H17NO3, (E,Z,E)‐1‐(4‐ethoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C20H19NO3, (E,Z,E)‐1‐(4‐nitrophenyl)‐6‐(4‐n‐propoxyphenyl)hexa‐1,3,5‐triene, C21H21NO3, and (E,Z,E)‐1‐(4‐n‐butoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C22H23NO3, have been determined. Intermolecular N⋯O dipole interactions between the nitro groups are observed for the methoxy derivative, while for the ethoxy derivative, two adjacent molecules are linked at both ends through N⋯O dipole–dipole interactions between the N atom of the nitro group and the O atom of the ethoxy group to form a supramolecular ring‐like structure. In the crystal structures of the n‐propoxy and n‐butoxy derivatives, the shortest intermolecular distances are those between the two O atoms of the alkoxy groups. Thus, the nearest two molecules form an S‐shaped supramolecular dimer in these crystal structures. 相似文献
9.
Andrei S. Batsanov 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):e269-e270
The molecule of 3,5‐difluoro‐4‐nitropyridine N‐oxide, C5H2F2N2O3, is twisted around the C—NO2 bond by 38.5 (1)°, while the 3,5‐diamino analogue, 3,5‐diamino‐4‐nitropyridine N‐oxide monohydrate, C5H6N4O3·H2O, adopts a planar conformation stabilized by intramolecular hydrogen bonds, with a significant redistribution of π electrons. 相似文献
10.
Simon J. Garden Fernando R. da Cunha Christopher Glidewell John N. Low Janet M. S. Skakle James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o12-o14
In 2‐hydroxy‐3‐iodo‐5‐nitrobenzaldehyde, C7H4INO4, the molecules are linked into sheets by a combination of C—H⋯O hydrogen bonds and two‐centre iodo–nitro interactions, and these sheets are linked by aromatic π–π stacking interactions. Molecules of 2,4‐diiodo‐6‐nitroanisole, C7H5I2NO3, are disordered, with the nitro group and one of the I substituents each occupying common sets of sites with 0.5 occupancy. The molecules are linked into isolated centrosymmetric dimeric units by a single iodo–nitro interaction. 相似文献
11.
Robert T. Stibrany Harvey J. Schugar Joseph A. Potenza 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):o354-o357
Two of the title compounds, namely (E)‐1,2‐bis(1‐methylbenzimidazol‐2‐yl)ethene, C18H16N4, (Ib), and (E)‐1,2‐bis(1‐ethylbenzimidazol‐2‐yl)ethene, C20H20N4, (Ic), consist of centrosymmetric trans‐bis(1‐alkylbenzimidazol‐2‐yl)ethene molecules, while 3‐ethyl‐2‐[(E)‐2‐(1‐ethylbenzimidazol‐2‐yl)ethenyl]benzimidazol‐1‐ium perchlorate, C20H21N4+·ClO4−, (II), contains the monoprotonated analogue of compound (Ic). In the three structures, the benzimidazole and benzimidazolium moieties are essentially planar; the geometric parameters for the ethene linkages and their bonds to the aromatic groups are consistent with double and single bonds, respectively, implying little, if any, conjugation of the central C=C bonds with the nitrogen‐containing rings. The C—N bond lengths in the N=C—N part of the benzimidazole groups differ and are consistent with localized imine C=N and amine C—N linkages in (Ib) and (Ic); in contrast, the corresponding distances in the benzimidazolium cation are equal in (II), consistent with electron delocalization resulting from protonation of the amine N atom. Crystals of (Ib) and (Ic) contain columns of parallel molecules, which are linked by edge‐over‐edge C—H⋯π overlap. The columns are linked to one another by C—H⋯π interactions and, in the case of (Ib), C—H⋯N hydrogen bonds. Crystals of (II) contain layers of monocations linked by π–π interactions and separated by both perchlorate anions and the protruding ethyl groups; the cations and anions are linked by N—H⋯O hydrogen bonds. 相似文献
12.
Satyen Saha 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o174-o177
The crystal structures of three 4‐amino derivatives of 7‐nitro‐2,1,3‐benzoxadiazole with increasing substituent ring size, viz. 7‐nitro‐4‐(pyrrolidin‐1‐yl)‐2,1,3‐benzoxadiazole, C10H10N4O3, 7‐nitro‐4‐(piperidin‐1‐yl)‐2,1,3‐benzoxadiazole, C11H12N4O3, and 4‐(azepan‐1‐yl)‐7‐nitro‐2,1,3‐benzoxadiazole, C12H14N4O3, have been determined in order to understand their photophysical behaviour. All three were found to crystallize in centrosymmetric space groups. There is considerable electron delocalization compared with the parent compound, although the five‐membered oxadiazole ring apparently does not participate in this. The length of the C—N bond between the amino N atom and the 7‐nitrobenzoxadiazole system is found to be shorter than in similar compounds, as is the C—Nnitro bond. In each structure, the nitro group lies in the plane of the benzoxadiazole unit. 相似文献
13.
Masashi Kawai Hidetaka Yuge Takeshi Ken Miyamoto 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):m581-m582
The title diphenylcarbene porphyrin complex (diphenylcarbenyl‐κC)(methanol‐κO)(5,10,15,20‐tetra‐p‐tolylporphyrinato‐κ4N)ruthenium(II) methanol solvate, [Ru(C13H10)(C48H36N4)(CH4O)]·CH4O, has a six‐coordinate Ru atom with a methanol molecule as the second axial ligand. The carbene fragment is slightly distorted from an ideal sp2 configuration, with a C(phenyl)—C(carbene)—C(phenyl) angle of 112.2 (3)°. The Ru—C bond length of 1.845 (3) Å is comparable with other carbene complexes. The two phenyl rings of the carbene ligand are perpendicular to the carbene plane. Methanol solvate molecules link the methanol ligands of adjacent porphyrin complexes via hydrogen bonds. 相似文献
14.
Hong Ryol Suh Hyung Sock Suh Sock Sung Yun Eun Kwang Lee Sung Kwon Kang 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):m202-m203
In the title compound, [Y(C6H3N2O5)3(H2O)3], the Y atom is nine‐coordinate with a slightly distorted tricapped trigonal prismatic coordination geometry. The YIII ion is coordinated to three bidentate 2,6‐dinitrophenolate ligands and three water molecules. The Y—O bond distances are in the range 2.217 (3)–2.754 (4) Å, with the Y—O distances from the nitro groups being longer than those from the water molecules and the phenol groups. The coordinated NO2 groups are almost coplanar with the benzene rings. 相似文献
15.
Vladimir N. Nesterov Tatiana V. Timofeeva Oleg Ya. Borbulevych Mikhail Yu. Antipin Ronald D. Clark 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):971-975
A combinatorial chemistry approach has been used to synthesize an array of Schiff bases, five of which, namely N‐[(E,2E)‐3‐(4‐methoxyphenyl)‐2‐propenylidene]‐3‐nitroaniline, C16H14N2O3, (1a), N‐[(E,2E)‐3‐(4‐methoxyphenyl)‐2‐propenylidene]‐4‐nitroaniline, C16H14N2O3, (2a), N‐{(E,2E)‐3‐[4‐(dimethylamino)phenyl]‐2‐propenylidene}‐3‐nitroaniline, C17H17N3O2, (1b), N‐{(E,2E)‐3‐[4‐(dimethylamino)phenyl]‐2‐propenylidene}‐4‐nitroaniline, C17H17N3O2, (2b), and N‐{(E,2E)‐3‐[4‐(dimethylamino)phenyl]‐2‐propenylidene}‐2‐methyl‐4‐nitroaniline, C18H19N3O2, (3b), have been structurally characterized. A stack structure is observed for (1a) and (1b) in the crystal phase. Experimental and calculated molecular structures are discussed for these compounds which belong to a chemical class having potential applications as non‐linear optical materials. 相似文献
16.
Christopher Glidewell John N. Low Manuel Melguizo Antonio Quesada 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(1):o14-o18
In 2‐amino‐4,6‐dimethoxy‐5‐nitropyrimidine, C6H8N4O4, the molecules are linked by one N—H⋯N and one N—H⋯O hydrogen bond to form sheets built from alternating R(8) and R(32) rings. In isomeric 4‐amino‐2,6‐dimethoxy‐5‐nitropyrimidine, C6H8N4O4, which crystallizes with Z′ = 2 in P, the two independent molecules are linked into a dimer by two independent N—H⋯N hydrogen bonds. These dimers are linked into sheets by a combination of two‐centre C—H⋯O and three‐centre C—H⋯(O)2 hydrogen bonds, and the sheets are further linked by two independent aromatic π–π‐stacking interactions to form a three‐dimensional structure. 相似文献
17.
Li Feng Zhi‐Ming Li Yong‐Sheng Tan Min‐Qin Chen Lin‐Hong Weng Feng‐Gang Tao 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):o473-o474
The title compound, dimethyl 10b′‐(4‐fluorostyryl)‐8′,9′‐dimethoxy‐4‐nitro‐5′,6′‐dihydrospiro[9H‐fluorene‐9,1′(10b′H)‐pyrrolo[2,1‐a]isoquinoline]‐2′,3′‐dicarboxylate, C38H31FN2O8, is a new photochromic tetrahydroindolizine. One of the C—C bonds at the spiro C atom is very long [1.630 (2) Å], thus explaining the photochromic behaviour. 相似文献
18.
Masood Parvez Moazzam Hussain Bhatti Saqib Ali Muhammad Mazhar Sajid Iqbal Qureshi 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):327-328
The Sn atom in the crystal structure of the title compound,catena‐poly[trimethyltin‐μ‐[(2,5‐dioxo‐2,5‐dihydropyrrol‐1‐yl)acetato‐O:O′]], [Sn(CH3)3(C6H4NO4)], adopts a distorted trigonal bipyramidal coordination geometry with three methyl groups defining the trigonal plane [mean Sn—C 2.117 (11) Å] and the axial positions occupied by O atoms from different carboxylate groups, with significantly different Sn—O bond lengths [2.207 (5) and 2.358 (6) Å]. The structure forms a polymeric chain of complex molecules linked via carboxylate moieties. 相似文献
19.
Hidetaka Yuge Takeshi Ken Miyamoto Tomofumi Kikuchi Yukihiro Iwasaki 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(12):m594-m596
In the first bis[ruthenium(II)–porphyrin]–dicarbene complex, μ‐[1,4‐phenylenebis(phenylmethylidene‐κC)]bis[(ethanol‐κO)(5,10,15,20‐tetra‐p‐tolylporphyrinato‐κ4N)ruthenium(II)] 1,2‐dichloroethane trisolvate, [Ru2(C20H14)(C48H36N4)2(C2H6O)2]·3C2H4Cl2, an inversion center is located at the center of the μ‐phenylene group, leading to a parallel arrangement for the pair of porphyrin ring systems. The bond lengths and angles compare favourably with literature values for ruthenium–porphyrin–monocarbene complexes; the Ru=C(carbene) bond length and the C(phenyl)—C(carbene)—C(phenylene) angle are 1.865 (3) Å and 112.3 (3)°, respectively. The RuII ion is displaced out of the C20N4 porphyrin least‐squares plane (by 0.2373 Å) toward the bridging ligand of the Ci‐symmetry dimer. The porphyrin ring systems of the dimer thus exhibit mildly domed conformations. 相似文献
20.
Sergiy V. Rosokha Jian Jiang Lu Sergey M. Dibrov Jay K. Kochi 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o464-o466
The title compound, C6H2N6O10·2C2H4Cl2, forms layered stacks of pentanitroaniline molecules, which possess twofold symmetry. The voids between these stacks are occupied by dichloroethane molecules, which reside near a 2/m symmetry element and display pseudo‐inversion symmetry. The C atoms in one of the two solvent molecules are threefold disordered. In the pentanitroaniline molecule, considerable distortion of the benzenoid ring, coupled with the short C—N(H2) bond and out‐of‐plane NO2 twistings, point to significant intramolecular `push–pull' charge transfer at the amino‐ and nitro‐substituted (ortho and para) positions, as theoretically quantified by natural bond orbital analysis of the π‐electron density. 相似文献