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1.
Jerzy Cieplik Janusz Pluta Tadeusz Lis Iwona Bryndal 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(5):o259-o261
Two polymorphic forms of the title compound, C24H20Cl2N4, were obtained and characterized using X‐ray crystal structure analysis. Colourless crystals of polymorph (Ia) were obtained from the oily mother residue. Recrystallization of polymorph (Ia) from an acetone–methanol mixture resulted in pale‐yellow crystals of polymorph (Ib). The major feature distinguishing the two polymorphic forms is their interaction modes, and hence their packing arrangements. In the crystal structure of polymorph (Ia), there are N—H⋯N hydrogen bonds and also aromatic π–π stacking interactions between molecules. The molecules of polymorph (Ib) are linked by N—H⋯Cl hydrogen bonds only. 相似文献
2.
Vladimir N. Nesterov Volodymyr V. Nesterov 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):o781-o785
Two new polymorph forms, (Ia) and (Ib), of the title compound, C14H17N3S, and its solvate with acetonitrile, C14H17N3S·0.25C2H3N, (Ic), have been investigated. Crystals of the two polymorphs were grown from different solvents, viz. ethanol and N,N‐dimethylformamide, respectively. The polymorphs have different orientations of the thioamide group relative to the CN substituent, with s‐cis and s‐trans geometry of the C=C—C=S diene fragment, respectively. Compound (Ic) contains two independent molecules, A and B, with s‐cis geometry, and the solvate molecule lies on a twofold axis. The core of each molecule is slightly non‐planar; the dihedral angles between the conjugated C=C—CN linkage and the phenyl ring, and between this linkage and the thioamide group are 13.4 (2) and 12.0 (2)° in (Ia), 14.0 (2) and 18.2 (2)° in (Ib), 2.3 (3) and 12.7 (4)° in molecule A of (Ic), and 23.2 (3) and 8.1 (4)° in molecule B of (Ic). As a result of strong conjugation between donor and acceptor parts, the substituted phenyl rings have noticeable quinoid character. In (Ib), there exists a very strong intramolecular steric interaction (H⋯H = 1.95 Å) between the bridging and thioamide parts of the molecule, which makes such a form less stable. In the crystal structure of (Ia), intermolecular N—H⋯N and N—H⋯S hydrogen bonds link molecules into infinite tapes along the [10] direction. In (Ib), such intermolecular hydrogen bonds link molecules into infinite (101) planes. In (Ic), intermolecular N—H⋯N hydrogen bonds link molecules A and B into dimers, which are connected via N—H⋯S hydrogen bonds and form infinite chains along the c direction. 相似文献
3.
Yao‐Cheng Shi Bei‐Bei Zhu Xiao‐Bi Jing 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):m559-m562
The molecules of N,N′‐bis(2‐pyridylmethyl)ferrocene‐1,1′‐diyldicarboxamide, [Fe(C12H11N2O)2], contain intramolecular N—H⋯N hydrogen bonds and are linked into sheets by three independent C—H⋯O hydrogen bonds. The molecules of the isomeric compound N,N′‐bis(3‐pyridylmethyl)ferrocene‐1,1′‐diyldicarboxamide lie across inversion centres, and the molecules are linked into sheets by a combination of N—H⋯N hydrogen bonds and π–π stacking interactions between pyridyl groups. 相似文献
4.
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
5.
Cem Cüneyt Ersanl idem Albayrak Mustafa Odabaolu Carsten Thne Ahmet Erdnmez 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o133-o135
The structure of the title compound, C18H20ClN3O5, displays the characteristic features of azobenzene derivatives. Intramolecular N—H⋯O, weak intramolecular C—H⋯O, and intermolecular O—H⋯O and C—H⋯O interactions influence the conformation of the molecules and the crystal packing. Intermolecular hydrogen bonds link the molecules into infinite chains, and the title compound adopts the keto–amine tautomeric form. The azobenzene moiety of the molecule has a trans configuration. The molecule is not planar, and the dihedral angle between the two phenyl rings is 35.6 (2)°. 相似文献
6.
S. Thamotharan V. Parthasarathi Ranju Gupta D. P. Jindal Anthony Linden 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o405-o407
The asymmetric unit of the title compound, C25H30FN3O·0.5CH3OH, contains four symmetry‐independent steroid and two methanol molecules. The conformations of the independent steroid molecules are very similar. Intermolecular O—H⋯O hydrogen bonds create two independent chains, each of which links two of the independent steroid molecules plus one methanol molecule via a co‐operative O—H⋯O—H⋯O—H pattern. Intermolecular C—H⋯O and C—H⋯F interactions are also observed. 相似文献
7.
Yu‐Xi Sun Ran Zhang Qing‐Mai Jin Xi‐Jing Zhi Xiao‐Ming Lü 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o467-o469
The two title compounds, both with formula C18H16ClN3O, are structurally similar Schiff bases derived from the condensation of 4‐chlorobenzaldehyde or 2‐chlorobenzaldehyde with 4‐aminoantipyrine in methanol solution. As expected, both compounds adopt trans configurations about the central C=N bonds. In the crystal structure of the 4‐chloro analogue, molecules are linked through weak C—H⋯O hydrogen bonds, forming chains running along the a axis. In the crystal structure of the 2‐chloro analogue, molecules are linked through weak C—H⋯O and C—H⋯Cl hydrogen bonds, forming layers parallel to the ab plane. 相似文献
8.
Christopher Glidewell John N. Low Susan A. McWilliam Janet M. S. Skakle James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o97-o99
In 2‐trifluoromethyl‐4‐nitroaniline, C7H5F3N2O2, (I), the molecules lie across a mirror plane in space group Pnma. The molecules are linked by paired N—H?O hydrogen bonds to form a C(8)[R(6)] chain of rings, pairs of which are linked into a molecular ladder by a single C—H?O hydrogen bond. The isomeric 3‐trifluoromethyl‐4‐nitroaniline, (II), has Z′ = 2 in space group P21/c. Each molecule is linked to four others by N—H?O hydrogen bonds to form sheets built from alternating R(12) and R(32) rings. 相似文献
9.
Vratislav Langer Miroslav Ko Dalma Gyepesov Juraj Kronek Jozef Lusto Mariana Sldkovi
ov 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(10):o602-o606
Crystal structures are reported for three isomeric compounds, namely 2‐(2‐hydroxyphenyl)‐2‐oxazoline, (I), 2‐(3‐hydroxyphenyl)‐2‐oxazoline, (II), and 2‐(4‐hydroxyphenyl)‐2‐oxazoline, (III), all C9H9NO2 [systematic names: 2‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (I), 3‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (II), and 4‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (III)]. In these compounds, the deviation from coplanarity of the oxazoline and benzene rings is dependent on the position of the hydroxy group on the benzene ring. The coplanar arrangement in (I) is stabilized by a strong intramolecular O—H⋯N hydrogen bond. Surprisingly, the 2‐oxazoline ring in molecule B of (II) adopts a 3T4 (C2TC3) conformation, while the 2‐oxazoline ring in molecule A, as well as that in (I) and (III), is nearly planar, as expected. Tetramers of molecules of (II) are formed and they are bound together via weak C—H⋯N hydrogen bonds. In (III), strong intermolecular O—H⋯N hydrogen bonds and weak intramolecular C—H⋯O hydrogen bonds lead to the formation of an infinite chain of molecules perpendicular to the b direction. This paper also reports a theoretical investigation of hydrogen bonds, based on density functional theory (DFT) employing periodic boundary conditions. 相似文献
10.
Christopher Glidewell John N. Low Janet M. S. Skakle James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o120-o124
Molecules of 2‐(2‐nitrophenylaminocarbonyl)benzoic acid, C14H10N2O5, are linked into centrosymmetric R(8) dimers by a single O—H⋯O hydrogen bond [H⋯O = 1.78 Å, O⋯O = 2.623 (2) Å and O—H⋯O = 178°] and these dimers are linked into sheets by a single aromatic π–π stacking interaction. The isomeric compound 2‐(4‐nitrophenylaminocarbonyl)benzoic acid crystallizes in two polymorphic forms. In the orthorhombic form (space group P212121 with Z′ = 1, crystallized from ethanol), the molecules are linked into sheets of R(22) rings by a combination of one N—H⋯O hydrogen bond [H⋯O = 1.96 Å, N⋯O = 2.833 (3) Å and N—H⋯O = 171°] and one O—H⋯O hydrogen bond [H⋯O = 1.78 Å, O⋯O = 2.614 (3) Å and O—H⋯O = 173°]. In the monoclinic form (space group P21/n with Z′ = 2, crystallized from acetone), the molecules are linked by a combination of two N—H⋯O hydrogen bonds [H⋯O = 2.09 and 2.16 Å, N⋯O = 2.873 (4) and 2.902 (3) Å, and N—H⋯O = 147 and 141°] and two O—H⋯O hydrogen bonds [H⋯O = 1.84 and 1.83 Å, O⋯O = 2.664 (3) and 2.666 (3) Å, and O—H⋯O = 166 and 174°] into sheets of some complexity. These sheets are linked into a three‐dimensional framework by a single C—H⋯O hydrogen bond [H⋯O = 2.45 Å, C⋯O = 3.355 (4) Å and C—H⋯O = 160°]. 相似文献
11.
Hugh W. Thompson Marie L. Cot Roger A. Lalancette 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(10):o727-o729
The title compound, (1R)‐4,7,7‐trimethyl‐3‐oxobicyclo[2.2.1]heptane‐2‐endo‐acetic acid, C12H18O3, like its lower homolog, forms carboxyl‐to‐ketone hydrogen‐bonding catemers (Z′ = 2) [O⋯O = 2.729 (5) and 2.707 (5) Å, and O—H⋯O = 165 and 170°] with screw‐related components. The two molecules of the asymmetric unit differ slightly in conformation and produce two counter‐aligned hydrogen‐bonding chains, both aligned with the b axis. Close intermolecular C—H⋯O=C contacts exist for the ketone group of one molecule and for both the ketone and carboxyl functions in the other. 相似文献
12.
Lionel E. Cheruzel Mark S. Mashuta Robert M. Buchanan 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):o361-o362
Crystallization of the title compound, C8H8N4O2, results in the formation of one‐dimensional chains of imidazole (im) molecules linked together by strong hydrogen bonds. The O⋯N(im) separation and O—H(⋯N) distance are 2.6906 (17) and 1.74 (2) Å, respectively, and the O—H⋯N angle is 173 (2)°. The one‐dimensional chains are weakly π stacked along the b axis, with centroid‐to‐centroid separations of 3.678 (2) Å between five‐ and six‐membered rings and 3.963 (2) Å between six‐membered rings. Each molecule is arranged around an inversion center. 相似文献
13.
Xiu‐Li You Cheng‐Rong Lu Yong Zhang De‐Chun Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):o693-o695
Molecular packing analyses were carried out on 15 crystal data sets of chloro‐substituted Schiff bases, including that of the title compound, C15H15ClN2. C—H⋯π and π–π interactions play a major role in the molecular self‐assembly in the crystal. The former interactions favor molecules assembling into a screw, with a non‐centrosymmetric crystal structure. When the molecular dipole is small, π–π interactions favor a parallel, but not usually antiparallel, mode of packing. Weak C—H⋯X hydrogen bonds (X = Cl or Br) and X⋯X interactions seem to be a secondary driving force in packing. The title molecule takes the trans form and the two benzene rings are twisted around the central linkage in opposite directions. In the crystal structure, molecules interact through C—H⋯π and π–π interactions, forming a `dimer' and further forming double chains along [001]. The double chains are extended along [10] through C—H⋯Cl hydrogen bonds, forming double layers in (010). In the third direction, there are only ordinary, weaker, van der Waals interactions, which explains the crystal habit (i.e. thin plate). 相似文献
14.
Simon J. Garden Marilza B. Corrêa Angelo C. Pinto James L. Wardell John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):o234-o238
In ethyl N‐[2‐(hydroxyacetyl)phenyl]carbamate, C11H13NO4, all of the non‐H atoms lie on a mirror plane in the space group Pnma; the molecules are linked into simple chains by a single C—H⋯O hydrogen bond. The molecules of ethyl N‐[2‐(hydroxyacetyl)‐4‐iodophenyl]carbamate, C11H12INO4, are linked into sheets by a combination of O—H⋯I and C—H⋯O hydrogen bonds and a dipolar I⋯O contact. Ethyl N‐[2‐(hydroxyacetyl)‐4‐methylphenyl]carbamate, C12H15NO4, crystallizes with Z′ = 2 in the space group P; pairs of molecules are weakly linked by an O—H⋯O hydrogen bond and these aggregates are linked into chains by two independent aromatic π–π stacking interactions. 相似文献
15.
Jerzy Ossowski Piotr Ku Christian Nther Peter G. Jones 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(7):o369-o371
The title compound, C24H24N2O2, crystallizes as a triclinic polymorph from dimethylformamide and a monoclinic polymorph from ethanol. In both forms, the molecule displays crystallographic inversion symmetry, and the packing involves translationally related `ladders' of molecules connected by N—H⋯O=C hydrogen bonds. Differences between the structures can be rationalized in terms of weak C—H⋯O contacts. Powder and differential scanning calorimetry investigations of new samples gave no evidence for the triclinic form, and it seems to represent a disappearing polymorph. 相似文献
16.
Madhukar Hemamalini Packianathan Thomas Muthiah Gabriele Bocelli Andrea Cantoni 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(4):o284-o286
In the title compound, C10H9N2+·C9H5INO4S−·2H2O, the 4,4′‐bipyridine molecule is protonated at one of the pyridine N atoms. These moieties self‐assemble into a supramolecular chain along the a axis through N—H⋯N hydrogen bonds. The quinolinol OH group acts as a donor with respect to a sulfonate O atom [O—H⋯O(sulfonate)] and acts as an acceptor with respect to a C—H group of ferron [C—H⋯O(hydroxy)], forming a supramolecular chain along the b axis. These two types of supramolecular chains (one type made up of bipyridine motifs and the other made up of sulfoxine motifs) interact viaπ–π stacking, generating a three‐dimensional framework. These chains are further crosslinked by C—H⋯O hydrogen bonds and O—H⋯O hydrogen bonds involving water molecules. 相似文献
17.
Tadeusz Lis Youssif Ebead Artur Sikorski Karol Krzymiski Jerzy Baejowski 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):o85-o87
The title compounds, C15H13ClN2·H2O, (I), and C19H13NO, (II), form monoclinic crystals. Arranged in a `head‐to‐tail' manner, the molecules of the amine form (I) lie along the b axis in layers that are linked by a network of hydrogen bonds involving the endocyclic N atom, the H atom at the exocyclic N atom and all the atoms of the solvent water molecule. Molecules of (II), with the phenoxy group nearly perpendicular to the acridine moiety, are arranged in pairs related by a center of symmetry and stabilized via two C—H⋯N contacts; the latter are linked via a network of further C—H⋯N contacts and non‐specific dispersive interactions. 相似文献
18.
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
19.
Onur ahin Orhan Büyükgüngr Selami amaz Nurhan Gümrüküolu Cihan Kantar 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):o643-o646
The title compounds, C10H12N4, (I), and C9H10N4, (II), have been synthesized and characterized both spectroscopically and structurally. The dihedral angles between the triazole and benzene ring planes are 26.59 (9) and 42.34 (2)°, respectively. In (I), molecules are linked principally by N—H⋯N hydrogen bonds involving the amino NH2 group and a triazole N atom, forming R44(20) and R24(10) rings which link to give a three‐dimensional network of molecules. The hydrogen bonding is supported by two different C—H⋯π interactions from the tolyl ring to either a triazole ring or a tolyl ring in neighboring molecules. In (II), intermolecular hydrogen bonds and C—H⋯π interactions produce R34(15) and R44(21) rings. 相似文献
20.
John N. Low James L. Wardell R. Alan Howie Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):o231-o233
The structure of the triclinic polymorph of acetone 2,4‐dinitrophenylhydrazone, C9H10N4O4, has been redetermined from diffraction data collected at 120 (2) K; the molecules are linked by C—H⋯O hydrogen bonds into centrosymmetric R22(10) dimers which are themselves linked into a chain by an aromatic π–π stacking interaction. In the monoclinic polymorph, which crystallizes with Z′ = 2 in the space group P21/n, one type of molecule forms dimers exactly as in the triclinic polymorph, while the other forms C(6) chains. 相似文献