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1.
The title compound, C11H11NO3, has two molecules in the asymmetric unit, which differ in the orientation of their side‐chain OH groups, allowing them to form intermolecular O—H...O hydrogen bonds to different acceptors. In one case, the acceptor is the OH group of the other molecule, and in the other case it is an imide O=C group. This is the first example in the N‐substituted phthalimide series in which independent molecules have different types of acceptor. Molecular‐orbital calculations place the greatest negative charge on the OH group.  相似文献   

2.
The title compound, 2C6H8NO+·SeO42−·2H2O, contains 4‐hydroxyanilinium cations, selenate(VI) anions and water molecules. One of the two independent cations is nearly planar (excluding the ammonium H atoms), while the other is markedly nonplanar, with the hydroxy and ammonium groups displaced from the plane of the benzene ring. This results from the antiparallel orientation of the cations, which interact through oppositely polarized ammonium and hydroxy groups. Ionic and hydrogen‐bonding interactions join the oppositely charged units into a three‐dimensional network. This work demonstrates the usefulness of 4‐aminophenol in the crystal engineering of organic–inorganic hybrid compounds.  相似文献   

3.
The structure of poly­[[(ethyl­enedi­amine‐κ2N,N′)­cobalt(II)]‐μ‐tetra­oxo­molyb­dato(VI)], [Co(C2H8N2)MoO4]n or [CoMoO4(C2H8N2)]n, is composed of puckered layers constructed from MoO4 tetrahedra and CoN2O4 octahedra, with the ethyl­enedi­amine ligand coordinated to the Co atom in a cis fashion. Each pair of cobalt sites forms a binu­clear edge‐sharing unit through a {Co2O2} interaction. The binuclear octahedral units are interconnected through the bridging MoO4 tetrahedra into a layer structure.  相似文献   

4.
In the title compound, 2C8H12N+·2C4H3N4O4·C8H11N, the anions are linked by paired N—H⋯N hydrogen bonds [H⋯N = 2.07 and 2.11 Å, N⋯N = 2.942 (3) and 2.978 (3) Å and N—H⋯N = 173 and 170°] and by paired N—H⋯O hydrogen bonds [H⋯O = 1.98 and 2.05 Å, N⋯O = 2.855 (3) and 2.917 (3) Å, and N—H⋯O = 173 and 167°] into chains of rings. These chains are linked into sheets by further N—H⋯O hydrogen bonds in which all of the donors are provided by the cations [H⋯O = 1.83–2.17 Å, N⋯O = 2.747 (3)–2.965 (3) Å and N—H⋯O = 141–168°]. The neutral amine molecule is pendent from the sheet and is linked to it by a single N—H⋯N hydrogen bond [H⋯N = 2.00 Å, N⋯N = 2.901 (3) Å and N—H⋯N = 175°].  相似文献   

5.
The crystal structures of the two isomers bis­(1‐phenyl­ethyl­ammonium) hexa­chloridostannate(IV) and bis­(2‐phenyl­ethyl­ammonium) hexa­chloridostannate(IV), both (C8H12N)2[SnCl6], exhibit alternating organic and inorganic layers, which inter­act via N—H⋯Cl hydrogen bonding. The inorganic layer contains an extended two‐dimensional hydrogen‐bonded sheet. The Sn atom in the 1‐phenylethyl­ammonium salt lies on an inversion centre.  相似文献   

6.
The crystal structure of the title compound [systematic name: (1S,3aR,6aS)‐2‐((2S)‐2‐{[(2S)‐2‐cyclohexyl‐2‐(pyrazine‐2‐carbonylamino)acetyl]amino}‐3,3‐dimethylbutanoyl)‐N‐[(3S)‐1‐(cyclopropylamino)‐1,2‐dioxohexan‐3‐yl]‐3,3a,4,5,6,6a‐hexahydro‐1H‐cyclopenta[c]pyrrole‐1‐carboxamide], C36H53N7O6, contains two independent molecules, which possess distinct conformations and a disordered cyclopenta[c]pyrrolidine unit. In the crystal, molecules are linked into helical chains via three‐point N—H...O hydrogen‐bond connections in which three NH and three carbonyl groups per molecule are utilized. The chiralities of the six stereocentres per molecule inferred from this study are in agreement with the synthetic procedure.  相似文献   

7.
8.
Doubly and triply hydrogen‐bonded supramolecular synthons are of particular interest for the rational design of crystal and cocrystal structures in crystal engineering since they show a high robustness due to their high stability and good reliability. The compound 5‐methyl‐2‐thiouracil (2‐thiothymine) contains an ADA hydrogen‐bonding site (A = acceptor and D = donor) if the S atom is considered as an acceptor. We report herein the results of cocrystallization experiments with the coformers 2,4‐diaminopyrimidine, 2,4‐diamino‐6‐phenyl‐1,3,5‐triazine, 6‐amino‐3H‐isocytosine and melamine, which contain complementary DAD hydrogen‐bonding sites and, therefore, should be capable of forming a mixed ADADAD N—H…S/N—H…N/N—H…O synthon (denoted synthon 3sN·S;N·N;N·O), consisting of three different hydrogen bonds with 5‐methyl‐2‐thiouracil. The experiments yielded one cocrystal and five solvated cocrystals, namely 5‐methyl‐2‐thiouracil–2,4‐diaminopyrimidine (1/2), C5H6N2OS·2C4H6N4, (I), 5‐methyl‐2‐thiouracil–2,4‐diaminopyrimidine–N,N‐dimethylformamide (2/2/1), 2C5H6N2OS·2C4H6N4·C3H7NO, (II), 5‐methyl‐2‐thiouracil–2,4‐diamino‐6‐phenyl‐1,3,5‐triazine–N,N‐dimethylformamide (2/2/1), 2C5H6N2OS·2C9H9N5·C3H7NO, (III), 5‐methyl‐2‐thiouracil–6‐amino‐3H‐isocytosine–N,N‐dimethylformamide (2/2/1), (IV), 2C5H6N2OS·2C4H6N4O·C3H7NO, (IV), 5‐methyl‐2‐thiouracil–6‐amino‐3H‐isocytosine–N,N‐dimethylacetamide (2/2/1), 2C5H6N2OS·2C4H6N4O·C4H9NO, (V), and 5‐methyl‐2‐thiouracil–melamine (3/2), 3C5H6N2OS·2C3H6N6, (VI). Synthon 3sN·S;N·N;N·O was formed in three structures in which two‐dimensional hydrogen‐bonded networks are observed, while doubly hydrogen‐bonded interactions were formed instead in the remaining three cocrystals whereby three‐dimensional networks are preferred. As desired, the S atoms are involved in hydrogen‐bonding interactions in all six structures, thus illustrating the ability of sulfur to act as a hydrogen‐bond acceptor and, therefore, its value for application in crystal engineering.  相似文献   

9.
In the title compound, [Fe(C5H5)(C8H13N)]2(SO4)·5H2O, the Fe—C bond lengths lie in the range 2.021 (3)–2.047 (2) Å. Inter­molecular N—H⋯O and O—H⋯O hydrogen bonds link the cations, sulfate anions and water mol­ecules into a two‐dimensional hydrogen‐bonded network, which stabilizes the crystal packing.  相似文献   

10.
Lamotrigine, an antiepileptic drug, has been complexed with three aromatic carboxylic acids. All three compounds crystallize with the inclusion of N,N‐dimethylformamide (DMF) solvent, viz. lamotriginium [3,5‐diamino‐6‐(2,3‐dichlorophenyl)‐1,2,4‐triazin‐2‐ium] 4‐iodobenzoate N,N‐dimethylformamide monosolvate, C9H8Cl2N5+·C7H4IO2·C3H7NO, (I), lamotriginium 4‐methylbenzoate N,N‐dimethylformamide monosolvate, C9H7Cl2N5+·C8H8O2·C3H7NO, (II), and lamotriginium 3,5‐dinitro‐2‐hydroxybenzoate N,N‐dimethylformamide monosolvate, C9H8Cl2N5+·C7H3N2O7·C3H7NO, (III). In all three structures, proton transfer takes place from the acid to the lamotrigine molecule. However, in (I) and (II), the acidic H atom is disordered over two sites and there is only partial transfer of the H atom from O to N. In (III), the corresponding H atom is ordered and complete proton transfer has occurred. Lamotrigine–lamotrigine, lamotrigine–acid and lamotrigine–solvent interactions are observed in all three structures and they thereby exhibit isostructurality. The DMF solvent extends the lamotrigine–lamotrigine dimers into a pseudo‐quadruple hydrogen‐bonding motif.  相似文献   

11.
In the title compound, C8H12N+·C2H4O5P, the anions are linked by two O—H⋯O hydrogen bonds [H⋯O both 1.75 Å, O⋯O = 2.5781 (15) and 2.5834 (15) Å, and O—H⋯O = 169 and 176°] into sheets built from alternating (8) and (32) rings. Each cation is linked to an anion sheet by three N—H⋯O hydrogen bonds [H⋯O = 1.88–2.04 Å, N⋯O = 2.7603 (16)–2.9334 (17) Å and N—H⋯O = 162–166°], such that all the cations pendent from one face of the sheet are of the R configuration, while all those pendent from the opposite face are of the S configuration.  相似文献   

12.
In crystalline thio­salicylic acid (2‐mercapto­benzoic acid), C7H6O2S, the carboxyl­ic acid groups form hydrogen‐bonded dimers, whereas the S—H groups form an infinite S—H?S—H?S—H hydrogen‐bond chain, with an S?S distance of 3.986 (3) Å.  相似文献   

13.
The crystal structure of the title compound, [Zn(C2H8N2)3][MoO4], is composed of [MoO4]2− anions and [Zn(en)3]2+ complex cations (en is ethyl­enediamine), both with symmetry 2, which are held together in a three‐dimensional network via hydrogen‐bonding inter­actions. The [Zn(en)3]2+ cations in the crystal structure exhibit two configurations, viz. Λ(δδδ) and Δ(λλλ), as a pair of enantiomers.  相似文献   

14.
Polyamides constituted by glycine residues have a peculiar structure characterized by the establishment of intermolecular hydrogen bonds along three different directions. Spherulites of polyglycine and nylons 2/3, 2/3/3, 2/6, and 2/11 have been obtained from evaporation of concentrated solutions or from the molten state. In all cases, a negative birefringence was detected. This fact differs from the observations on spherulites of conventional nylons where intermolecular hydrogen bonds are formed along a single direction and sheet structures are postulated. Polarizing light, scanning electron, and transmission electron microscopy showed that banded spherulites are usually formed in the crystallization of nylons 2/n. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1719–1726, 2002  相似文献   

15.
In the ternary title compound, catena‐poly­[[silver(I)‐μ‐ethylenedi­amine‐κ2N:N′] 3‐nitro­benzoate monohydrate], {[Ag(C2H8N2)](C7H4NO4)·H2O}n, the Ag atom is bicoordinated in a linear configuration by two different N atoms from two symmetry‐related ethyl­enedi­amine ligands, thus giving linear polymeric chains with an [–Ag—N—C—C—N–]n backbone running parallel to the a axis. In the crystal packing, these linear chains are interconnected by N—H⃛O and O—H⃛O hydrogen bonds to form layers parallel to the ab plane.  相似文献   

16.
17.
The title 1,2‐diol derivative, C10H12O2, crystallizes with two independent but closely similar mol­ecules in the asymmetric unit. Only two of the four OH groups are involved in classical hydrogen bonding; the mol­ecules thereby associate to form chains parallel to the short c axis. The other two OH groups are involved in O—H⋯(C[triple‐bond]C) systems. Additionally, three of the four C[triple‐bond]C—H groups act as donors in C—H⋯O inter­actions. The 1,4‐diol derivative crystallizes with two independent half‐mol­ecules of the diol (each associated with an inversion centre) and one water mol­ecule in the asymmetric unit, C12H16O2·H2O. Both OH groups and one water H atom act as classical hydrogen‐bond donors, leading to layers parallel to the ac plane. The second water H atom is involved in a three‐centre contact to two C[triple‐bond]C bonds. One acetyl­enic H atom makes a very short `weak' hydrogen bond to a hydr­oxy O atom, and the other is part of a three‐centre system in which the acceptors are a hydroxy O atom and a C[triple‐bond]C bond.  相似文献   

18.
The title complexes, (C3H12N2)[WS4] and (C6H18N2)[WS4], contain tetrahedral [WS4]2− dianions, which accept a complex series of hydrogen bonds from the organic dications. The strength and number of these hydrogen bonds affect the W—S distances.  相似文献   

19.
Poly(ethylethylene‐b‐ethylene oxide) (PEE‐PEO) diblock copolymers with pyridine‐benzoic acid end‐groups for heterodimeric hydrogen bonding were designed as a possible means to noncentrosymmetric organizations by spontaneous self‐assembly. These end‐functionalized polymers were synthesized by anionic living polymerization with protected initiator and terminating reagents. A series of polymeric intermediates with different end‐groups was characterized by proton nuclear magnetic resonance, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry, and gel permeation chromatography. Preliminary studies of solid‐state organization by differential scanning calorimetry and small‐angle X‐ray scattering provided evidence for a long‐range order that was sensitive to chain length, copolymer composition, and end‐group structure. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 207–219, 2000  相似文献   

20.
The structure of rubidium gadolinium bis­(tungstate), RbGd(WO4)2, has been determined. The crystal is built up from corner‐ and edge‐sharing WO6 octa­hedral and GdO8 polyhedral groups, giving rise to a Gd–WO4 polyhedral backbone surrounding structural cavities filled with Rb+ cations. The Gd and Rb atoms lie on twofold axes.  相似文献   

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