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1.
Two new glycoluril derivatives, namely diethyl 6‐ethyl‐1,4‐dioxo‐1,2,2a,3,4,6,7,7b‐octahydro‐5H‐2,3,4a,6,7a‐pentaazacyclopenta[cd]indene‐2a,7b‐dicarboxylate, C14H21N5O6, (I), and 6‐ethyl‐2a,7b‐diphenyl‐1,2,2a,3,4,6,7,7b‐octahydro‐5H‐2,3,4a,6,7a‐pentaazacyclopenta[cd]indene‐1,4‐dione, C20H21N5O2, (II), both bearing two free syn‐urea NH groups and two ureidyl C=O groups, assemble the same one‐dimensional chains in the solid state running parallel to the [010] direction via N—H...O hydrogen bonds. Furthermore, the chains of (I) are linked together into two‐dimensional networks via C—H...O hydrogen bonds.  相似文献   

2.
The title compound, N‐hydroxy­propan­amide, C3H7NO2, crystallizes with Z′ = 3 in P21/c. The mol­ecules are linked by three N—H?O hydrogen bonds [N?O 2.8012 (16) to 2.8958 (15) Å; N—H?O 163 to 168°] and by three O—H?O hydrogen bonds [O?O 2.6589 (15) to 2.6775 (17) Å; O—H?O 165 to 177°] into a single three‐dimensional framework.  相似文献   

3.
The title compound (C6H7NO3S) exists as a zwitterion (4‐ammonio­benzene­sulfonate), +H3NC6H4SO3?, and these units are linked into a three‐dimensional framework by two distinct two‐centre N—H?O hydrogen bonds [H?O 1.84 and 1.87 Å; N?O 2.767 (2) and 2.746 (2) Å; N—H?O 166 and 172°] and a planar three‐centre N—H?(O)2 hydrogen bond [H?O 2.03 and 2.37 Å; N?O 2.816 (2) and 2.877 (2) Å; N—H?O 162 and 111°; O?H?O 86°].  相似文献   

4.
In the title compound, C6H18N22+·2C2H2ClO2, the cation lies across an inversion centre in the P space group. The ions are linked by two two‐centre N—H...O hydrogen bonds and by one three‐centre N—H...(O)2 hydrogen bond to form a three‐dimensional framework structure. The significance of this study lies in the analysis of the complex hydrogen‐bonded structure and in the comparison of this structure with those of other simple hexamethylenediammonium salts.  相似文献   

5.
A novel three‐dimensional framework of 2‐[(1H‐imidazol‐1‐yl)methyl]‐1H‐benzimidazole dihydrate, C11H10N4·2H2O or L·2H2O, (I), in which L acts as both hydrogen‐bond acceptor and donor in the supramolecular construction with water, has been obtained by self‐assembly reaction of L with H2O. The two independent water molecules are hydrogen bonded alternately with each other to form a one‐dimensional infinite zigzag water chain. These water chains are linked by the benzimidazole molecules into a three‐dimensional framework, in which each organic molecule is hydrogen bonded by three water molecules. This study shows that the diversity of hydrogen‐bonded patterns plays a crucial role in the formation of the three‐dimensional framework. More significantly, as water molecules are important in contributing to the conformation, stability, function and dynamics of biomacromolecules, the infinite chains of hydrogen‐bonded water molecules seen in (I) may be a useful model for water in other chemical and biological processes.  相似文献   

6.
The structures of 3‐amino‐1,2R,4S,5‐tetra­ammoniopentane tetrachloride monohydrate, C5H21N54+·4Cl?·H2O, and 1,2R,3,4S,5‐penta­ammoniopentane tetra­chloro­zincate tri­chlor­ide monohydrate, (C5H22N5)[ZnCl4]Cl3·H2O, have been determined from single‐crystal X‐ray diffraction data. Both compounds show a complex network of N—H?O, O—H?Cl and N—H?Cl hydrogen bonds. There are a total of 14 H atoms of the tetra‐cation and 15 H atoms of the penta‐cation available for hydrogen bonding. However, due to the particular shape of the primary linear poly­ammonium cations, only a certain number of H atoms can be involved in hydrogen‐bond formation. It is further shown that hydrogen bonding has an influence on the conformation of such alkyl­ammonium cations.  相似文献   

7.
The nature of the interactions of cyanide with lithium and hydrogen halides was investigated using ab initio calculations and topological analysis of electron density. The computed properties of the lithium‐bonded complexes RCN···LiX (R = H, F, Cl, Br, C?CH, CH?CH2, CH3, C2H5; X = Cl, Br) were compared with those of corresponding hydrogen‐bonded complexes RCN···HX. The results show that both types of intermolecular interactions are “closed‐shell” noncovalent interactions. The effect of substitution on the interaction energy and electron density at the bond critical points of the lithium and hydrogen bonding interactions is similar. In comparison, the interaction energies of lithium‐bonded complexes are more negative than those of hydrogen‐bonded counterparts. The electrostatic interaction plays a more important role in the lithium bond than in the hydrogen bond. On complex formation, the net charge and energy of the Li atom decrease and the atomic volume increases, while the net charge and energy of the H atom increase and the atomic volume decreases. © 2013 Wiley Periodicals, Inc.  相似文献   

8.
Polymorph VI of 4‐amino‐N‐(2‐pyridyl)benzenesulfonamide, C11H11N3O2S, is monoclinic (space group P21/n). The asymmetric unit contains two different tautomeric forms. The structure displays N—H...N and N—H...O hydrogen bonding. The two independent molecules form two separate two‐ and three‐dimensional hydrogen‐bonded networks which interpenetrate. The observed patterns of hydrogen bonding are analogous to those in polymorph I of sulfathiazole.  相似文献   

9.
The mol­ecular structures of the complexes imidazolium 6,6′‐di‐tert‐butyl‐4,4′‐dimethyl‐2,2′‐thio­diphenyl phosphate, C3H5N2+·C22H28O4PS, (I), and imidazolium 6,6′‐di‐tert‐butyl‐4,4′‐dimethyl‐2,2′‐thio­diphenyl phosphate diisopropyl hydrazo­dicarboxyl­ate hemisolvate, C3H5N2+·C22H28O4PS·0.5C8H16N2O4, (II), have been determined. While (I) forms the expected hydrogen‐bonded chain utilizing the two imidazole N‐bound H atoms, in (II), the substituted hydrazine solvent mol­ecule inserts itself between the chains. Compound (I) exhibits a strong N—H⋯O hydrogen bond, with an N⋯O distance of 2.603 (2) Å. The hydrazine solvent molecule in (II) lies about a twofold axis and the N‐bound H atoms are involved in bifurcated hydrogen bonds with phosphate O atoms. A C‐bound H atom of the imidazolium cation is involved in a C—H⋯O inter­action with a carbonyl O atom of the hydrazine solvent mol­ecule.  相似文献   

10.
The title compound, 4,4′‐(1,1,1,3,3,3‐hexafluoroisopropylidene)diphthalic acid hexahydrate, C19H10F6O8·6H2O, crystallizes in the centrosymmetric space group Pbcn, with half of the diphthalic acid residue and three water molecules in the asymmetric unit. The organic molecule is located on a crystallographic twofold axis. In the solid, cyclic water hexamers in chair conformations have crystallographically imposed inversion symmetry. Strong O—H...O hydrogen bonds between the hexamers and organic molecules result in a unique three‐dimensional supramolecular network [O...O = 2.554 (2)–2.913 (2) Å]. This compound represents the first example of a (3,4,4,10)‐connected four‐nodal supramolecular topology with the Schläfli symbol (43.5.6.7)2(43.52.7)2(43)2(46.56.62.78.814.99).  相似文献   

11.
In the title compound, C4H6N4S·0.5H2O, there are two independent pyrimidinethione units, both of which lie across mirror planes in the space group Cmca. Hence, the H atoms bonded to the ring N atoms in each molecule are disordered over two symmetry‐related sites, each having an occupancy of 0.5. The water molecule lies across a twofold rotation axis parallel to [010]. The molecular components of (I) are linked by seven independent hydrogen bonds, of N—H...N, N—H...S, N—H...O and O—H...S types. A combination of disordered N—H...N hydrogen bonds and ordered N—H...S hydrogen bonds links the pyrimidinethione units into a continuous tubular structure. The water molecule acts as both a double donor of hydrogen bonds and a double acceptor, forming hydrogen bonds with components of four distinct pyrimidinethione tubes, thus linking these tubes into a three‐dimensional structure.  相似文献   

12.
The structures of two salts of flunarizine, namely 1‐bis[(4‐fluorophenyl)methyl]‐4‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazine, C26H26F2N2, are reported. In flunarizinium nicotinate {systematic name: 4‐bis[(4‐fluorophenyl)methyl]‐1‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazin‐1‐ium pyridine‐3‐carboxylate}, C26H27F2N2+·C6H4NO2, (I), the two ionic components are linked by a short charge‐assisted N—H...O hydrogen bond. The ion pairs are linked into a three‐dimensional framework structure by three independent C—H...O hydrogen bonds, augmented by C—H...π(arene) hydrogen bonds and an aromatic π–π stacking interaction. In flunarizinediium bis(4‐toluenesulfonate) dihydrate {systematic name: 1‐[bis(4‐fluorophenyl)methyl]‐4‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazine‐1,4‐diium bis(4‐methylbenzenesulfonate) dihydrate}, C26H28F2N22+·2C7H7O3S·2H2O, (II), one of the anions is disordered over two sites with occupancies of 0.832 (6) and 0.168 (6). The five independent components are linked into ribbons by two independent N—H...O hydrogen bonds and four independent O—H...O hydrogen bonds, and these ribbons are linked to form a three‐dimensional framework by two independent C—H...O hydrogen bonds, but C—H...π(arene) hydrogen bonds and aromatic π–π stacking interactions are absent from the structure of (II). Comparisons are made with some related structures.  相似文献   

13.
In this study, the seGVB method was implemented for the N H bonding system, specifically for hydrogen‐bonded ammonia complexes, and the model well reproduces the MP2 geometries and energetics. A comparison between the ammonia dimer and water dimer is given from the viewpoint of valance‐bond structures in terms of the calculated bond energies and pair–pair interactions. The linear hydrogen bond is found to be stronger than the bent bonds in both cases, with the difference in energy between the linear and cyclic structures being comparable in both cases although the NH bonds are generally weaker. The energy decomposition clearly demonstrates that the changes in electronic energy are quite different in the two cases due to the presence of an additional lone pair on the water molecule, and it is this effect which leads to the net stabilization of the cyclic structure for the ammonia dimer. Proton‐transfer profiles for hydrogen‐bonded ammonia complexes [NH2 H NH2] and [NH3 H NH3]+ were calculated. The barrier for proton transfer in [NH3 H NH3]+ is larger than that in [NH2 H NH2], but smaller than that in the protonated water dimer. The different bonding structures substantially affect the barrier to proton transfer, even though they are isoelectronic systems. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 73: 357–367, 1999  相似文献   

14.
Molecules of 2,4‐dimethylbenzoic acid, C9H10O2, form typical centrosymmetric hydrogen‐bonded dimers. The carboxyl group is twisted with respect to the benzene ring and the methyl group in the ortho position shows evasive in‐plane splaying. The relation between the in‐plane splaying and the twist angle of the carboxyl group for various ortho‐substituted dimeric derivatives of benzoic acid is presented. It shows how the steric strains are released depending on the numbers and positions of the substituents.  相似文献   

15.
In the title compound (systematic name: N‐anilino‐4‐nitrobenzamide), C13H11N3O3, the molecules are linked into a complex three‐dimensional framework structure by a combination of two‐centre N—H...O and C—H...O hydrogen bonds and a three‐centre N—H...(O,N) hydrogen bond.  相似文献   

16.
Crystals of the title compound, 2C3H7N6+·C10H6O6S22−·C3H6N6·5H2O, are built up of neutral 2,4,6‐triamino‐1,3,5‐triazine (melamine), singly protonated melaminium cations, naphthalene‐1,5‐disulfonate dianions and water molecules. Two independent anions lie across centres of inversion in the space group P. The melamine molecules are connected by N—H...N hydrogen bonds into two different one‐dimensional polymers almost parallel to the (010) plane, forming a stacking structure along the b axis. The centrosymmetric naphthalene‐1,5‐disulfonate anions interact with water molecules via O—H...O hydrogen bonds, forming layers parallel to the (001) plane. The cations and anions are connected by N—H...O and O—H...N hydrogen bonds to form a three‐dimensional supramolecular framework.  相似文献   

17.
In the P polymorph of benzanilide or N‐phenyl­benz­amide, C13H11NO, the mol­ecules are linked into simple C(4) chains by N—H⋯O hydrogen bonds. The mol­ecules exhibit orientational disorder, but the donor and acceptor in a given hydrogen bond may occur, independently, in either the major or the minor orientation, such that all four possible N—H⋯O combinations have very similar geometries. The structure of this P polymorph can be related to that of a previously reported C2/c polymorph.  相似文献   

18.
The title compound, C3H7NO2·C3H8NO2+·NO3?, contains l ‐alanine–alaninium dimers bonded via the carboxyl groups by a strong asymmetric hydrogen bond with an O?O distance of 2.4547 (19) Å. The neutral alanine mol­ecule exists as a zwitterion, where the carboxyl group is dissociated and the amino group is protonated. The alaninium cation has both groups in their acidic form. The alanine mol­ecule and the alaninium cation differ only slightly in their conformation, having an N—Cα—C=O torsion angle close to ?25°. The dimers and the nitrate anion are joined through a three‐dimensional hydrogen‐bond network, in which the full hydrogen‐bonding capabilities of the amino groups of the two alanine moieties are realised.  相似文献   

19.
The molecules of 5‐amino‐1‐(4‐methoxybenzoyl)‐3‐methylpyrazole, C12H13N3O2, (I), and 5‐amino‐3‐methyl‐1‐(2‐nitrobenzoyl)pyrazole, C11H10N4O3, (II), both contain intramolecular N—H...O hydrogen bonds. The molecules of (I) are linked into a chain of rings by a combination of N—H...N and N—H...π(arene) hydrogen bonds, while those of (II) are linked into a three‐dimensional framework structure by N—H...N and C—H...O hydrogen bonds.  相似文献   

20.
1,5‐Bis(4‐chlorophenyl)‐3‐(2‐oxo‐1,2‐dihydroquinolin‐3‐yl)pentane‐1,5‐dione, (Ia), and 1,5‐bis(2‐chlorophenyl)‐3‐(2‐oxo‐1,2‐dihydroquinolin‐3‐yl)pentane‐1,5‐dione, (Ib), crystallize as an 84:16 mixture, 0.84C26H19Cl2NO3·0.16C26H19Cl2NO3, in the space group I41/a, where the molecules of the two isomers occupy very similar sites in the unit cell. A combination of one N—H...O hydrogen bond and one C—H...O hydrogen bond links the molecules, regardless of isomeric form, into a single three‐dimensional framework structure. The molecules of (9RS,10RS)‐8,9‐bis(4‐chlorobenzyl)‐10‐(2‐oxo‐1,2‐dihydroquinolin‐3‐yl)‐5,6,9,10‐tetrahydrophenanthridine, C36H22Cl2N2O4, (II), are linked by two hydrogen bonds, one each of the N—H...O and C—H...O types, into a molecular ribbon in which centrosymmetric rings of R22(18) and R44(24) types alternate. The hydrogen‐bonded ribbons enclose channels, which contain highly disordered solvent molecules.  相似文献   

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