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1.
Annegret K. Hall Jack M. Harrowfield Brian W. Skelton Allan H. White 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):407-411
The sodium salt of a complex anion formed between gadolinium(III) and three variously deprotonated chelidamic acid (4‐hydroxypyridine‐2,6‐dicarboxylic acid) ligand moieties, assigned as Na5[Gd(C7H2NO5)2(C7H3NO5)]·16H2O, i.e. pentasodium (4‐hydroxypyridine‐2,6‐dicarboxylate)bis(4‐oxidopyridine‐2,6‐dicarboxylate)gadolinium(III) hexadecahydrate, forms as colourless monoclinic crystals upon vapour diffusion of ethanol into its aqueous solution. The ligand moieties, assigned as two trianionic and one dianionic chelidamate species, are all tridentate in the complex anion of tricapped trigonal prismatic donor‐atom geometry. The geometry of the ligands and that of the primary coordination sphere is very similar to that of the analogous anionic tris(ligand)–rare earth complexes of the pyridine‐2,6‐dicarboxylate (dipicolinate) dianion. 相似文献
2.
Nobuo Okabe Naomi Oya 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):1416-1417
In the structure of the title compound, [Mn2(C7H3NO4)2(H2O)6]·2C7H5NO4, a centrosymmetric dinuclear complex, hexaaaquabis(pyridine‐2,6‐dicarboxylato)dimanganese(II) and free pyridine‐2,6‐dicarboxylic acid are present in a 1:2 ratio. In the complex, each Mn2+ ion is coordinated by three O atoms and one N atom from the pyridine‐2,6‐dicarboxylate ligands and by three water O atoms, resulting in a distorted pentagonal bipyramidal coordination. Within the centrosymmetric dinuclear complex, two Mn2+ ions are bridged by two carboxylate O atoms. The crystal structure is stabilized by hydrogen bonds involving all the H atoms of the water ligands. 相似文献
3.
Sara K. Metcalf Elizabeth M. Holt 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):1228-1231
Diethyl 4‐(2,5‐dimethoxyphenyl)‐2,6‐dimethyl‐1,4‐dihydropyridine‐3,5‐dicarboxylate, C21H27NO6, (I), diethyl 4‐(3,4‐dimethoxyphenyl)‐2,6‐dimethyl‐1,4‐dihydropyridine‐3,5‐dicarboxylate, C21H27NO6, (II), and diethyl 2,6‐dimethyl‐4‐(3,4,5‐trimethoxyphenyl)‐1,4‐dihydropyridine‐3,5‐dicarboxylate, C22H29NO7, (III), crystallize with hydrogen‐bonding networks involving the H atom bonded to the N atom of the 1,4‐dihydropyridine ring and carbonyl O atoms in (I) and (II). Unusually, (III) shows O atoms of methoxy groups serving as hydrogen‐bond acceptors. 相似文献
4.
Vladimir Carranza Tllez Brenda Snchez Gaytn Sylvain Berns Enrique Gonzlez Vergara 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):o228-o230
The structure of pyridine‐2,6‐dicarboxylic acid, C7H5NO4, has been determined at 0.71 Å resolution. The molecule is located on a site with mirror symmetry. A one‐dimensional supramolecular structure is stabilized in the solid state through a strong symmetric double hydrogen bond, with H?O distances of 1.86 (3) Å and O—H?O angles of 167 (3) and 171 (5)°. This arrangement is similar but not identical to that reported for the isoelectronic isophthalic acid (benzene‐1,3‐dicarboxylic acid). 相似文献
5.
Chun‐Bo Liu Guang‐Bo Che Chuan‐Bi Li Yun‐Cheng Cui 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):m153-m155
An in situ reaction under hydrothermal conditions leads to the formation of the title compound, diaqua(pyridine‐2‐carboxylato)(pyridine‐2,6‐dicarboxylato)indium(II) trihydrate, [In(C6H4NO2)(C7H3NO4)(H2O)2]·3H2O, in which the central InIII atom is seven‐coordinated by one pyridine‐2,6‐dicarboxylate ligand, one pyridine‐2‐carboxylate ligand and two water molecules in a pentagonal–bipyramidal coordination environment. An indium(III)–water chain based on an unusual water pentamer is observed. 相似文献
6.
Wen‐Na Zhao Jian‐Wei Zou Qing‐Shen Yu 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):m443-m444
The title one‐dimensional chain nickel(II)–disulfide complex, [Ni(C14H8O4S2)(C5H5N)2(H2O)]n, has each NiII cation coordinated by two N atoms from two pyridine ligands, three carboxylate O atoms from two different dithiodibenzoate ligands and one O atom from a coordinated water molecule, in a distorted octahedral coordination geometry. Each dithiodibenzoate ion links two NiII cations through its carboxylate O atoms, making the structure polymeric. Hydrogen‐bond interactions between two shoulder‐to‐shoulder chains lead to the formation of a ladder‐like structure. 相似文献
7.
Hong‐Tao Zhang Ting Shao Hua‐Qin Wang Xiao‐Zeng You 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):m259-m261
The asymmetric unit of the title compound, {[Ni(C12H6N2O4)(H2O)3]·H2O}n, is composed of a lattice water molecule and a nickel(II) ion that is coordinated by three water molecules and the two N atoms of a 2,2′‐bipyridine‐3,3′‐dicarboxylate ligand. The twist of the 2,2′‐bipyridine‐3,3′‐dicarboxylate unit and the coordination of one carboxylate group to a symmetry‐related NiII atom generate a helical chain that runs along the b axis. Intrahelical hydrogen bonds participate in controlling the orientation of the helices, and both right‐handed and left‐handed helices are connected by interhelical hydrogen bonds into two‐dimensional sheets. 相似文献
8.
Michael Bolte Alexander Degen Ernst Egert 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1338-1342
We have determined the crystal structures of bicyclo[2.2.1]hept‐2‐ene‐endo‐cis‐5,6‐dicarboxylic anhydride, C9H8O3, (I), 1,2,3,4,7,7‐hexachlorobicyclo[2.2.1]hept‐2‐ene‐endo‐cis‐5,6‐dicarboxylic anhydride diethyl ether solvate, C9H2Cl6O3·0.16C4H10O, (II), bicyclo[2.2.1]hept‐2‐ene‐endo‐cis‐5,6‐dicarboxylic acid, C9H10O4, (III), 1,2,3,4,7,7‐hexachlorobicyclo[2.2.1]hept‐2‐ene‐endo‐cis‐5,6‐dicarboxylic acid, C9H4Cl6O4, (IVa) and (IVb), and ethyl 1,2,3,4,7,7‐hexachloro‐6‐carboxybicyclo[2.2.1]hept‐2‐ene‐endo‐cis‐5‐carboxylate monohydrate, C11H8Cl6O4·H2O, (V). Compounds (I) and (II) were prepared by a standard Diels–Alder reaction from maleic anhydride and cyclopentadiene or hexachlorocyclopentadiene, respectively. The crystal‐growing processes of these compounds led to surprising results: rapid recrystallization of (I) from diethyl ether and (II) from petroleum ether gave crystals of these compounds, however, crystallization by slow evaporation techniques using common solvents yielded new compounds in which the five‐membered heterocycle has been cleaved. 相似文献
9.
Seik Weng Ng S. Shanmuga Sundara Raj Hoong‐Kun Fun Ibrahim Abdul Razak James M. Hook 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):966-968
catena‐Poly[dicyclohexylammonium [tributyltin‐μ‐(4‐oxo‐4H‐pyran‐2,6‐dicarboxylato‐O2:O6)]], (C12H24N)[Sn(C7H2O6)(C4H9)3], consists of 4‐oxo‐4H‐pyran‐2,6‐dicarboxylato groups that axially link adjacent tributyltin units into a linear polyanionic chain. The ammonium counter‐ions surround the chain, and each cation forms a pair of hydrogen bonds to the double‐bond carbonyl O atoms of the same dianionic group. The chain propagates in a zigzag manner along the c axis of the monoclinic cell. In catena‐poly[methyl(phenyl)ammonium [tributyltin‐μ‐(pyridine‐2,6‐dicarboxylato‐O2:O6)]], (C7H10N)[Sn(C7H3NO4)(C4H9)3], the pyridine‐2,6‐dicarboxylato groups also link the tributyltin groups into a chain, but the hydrogen‐bonded chain propagates linearly on the ac face of the monoclinic cell. 相似文献
10.
Alessandra Crispini Francesco Neve 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):o34-o35
The distinctive feature of the crystal structure of 2,6‐diphenylpyridine‐4‐carboxylic acid, C18H13NO2, is the formation of intermolecular O—H?O hydrogen bonds that lead to the formation of centrosymmetric cyclic dimers with R(8) topology. Molecules related by translation along the b axis exhibit strong π–π stacking of aromatic rings, with an average interplanar distance of 3.3 Å. 相似文献
11.
E. Yang Zhao‐Ji Li Jian Zhang Yu‐Biao Chen Yuan‐Gen Yao 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):m457-m459
The reaction of cadmium chloride with pyridine‐2,6‐dicarboxylic acid (PDA) and 98% H2SO4 in ethanol led to the formation of the title compound, bis[μ‐6‐(ethoxycarbonyl)pyridine‐2‐carboxylato]‐1:2κ4O6,N,O2:O2;1:2κ4O2:O2,N,O6‐bis[diaquachlorocadmium(II)] dihydrate, [Cd2(C9H8NO4)2Cl2(H2O)4]·2H2O. PDA is esterified to monoethyl pyridine‐2,6‐dicarboxylate (MEPD) by the catalysis of H2SO4 during the reaction. The dinuclear CdII complex lies about an inversion centre and the unique Cd atom has a pentagonal–bipyramidal geometry. The two Cd atoms are bridged by two carboxylate O atoms, forming a planar Cd2O2 unit. Stair‐like chains are formed via O—H⋯Cl hydrogen bonds and these are further arranged into two‐dimensional layers via hydrogen bonds involving solvate water molecules. 相似文献
12.
Hong‐Tao Zhang Xiao‐Zeng You 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):m313-m314
The asymmetric unit of the title one‐dimensional coordination polymer, catena‐poly[[μ‐pyridine‐2,3‐dicarboxylato‐1κO:2κ2N,O′‐bis[diaquacobalt(II)]]‐μ‐pyridine‐2,3‐dicarboxylato‐1κ2N,O:2κO′:1′κO′], [Co(C7H3NO4)(H2O)2]n, is composed of a cobalt(II) ion, a pyridine‐2,3‐dicarboxylate dianion and two water molecules. The polymer has a zigzag structure consisting of a chain of edge‐fused rings, and the polymer chains are linked by O—H⃛O hydrogen bonds into a three‐dimensional framework. 相似文献
13.
The title compounds, bis(pyridine‐2,6‐dicarboxylato‐N,O,O′)copper(II) monohydrate, [Cu(C7H4NO4)2]·H2O, andbis(pyridine‐2,6‐dicarboxylato‐N,O,O′)zinc(II) trihydrate, [Zn(C7H4NO4)2]·3H2O, have distorted octahedral geometries about the metal centres. Both metal ions are bonded to four O atoms and two pyridyl‐N atoms from the two terdentate ligand molecules, which are nearly perpendicular to each other. The copper(II) complex has twofold crystallographic symmetry and contains two different ligand molecules, one of which is neutral and another doubly ionized. In contrast, the zinc(II) complex contains two identical singly ionized ligand molecules. Both crystal structures are stabilized by O—H?O intermolecular hydrogen bonds between the complex and the water molecules. 相似文献
14.
Elena Buuel Carlos Cativiela María D. Díaz‐de‐Villegas Jos A. Glvez 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):587-591
The structures of two conformationally restricted 4,5‐dihydroxynorvaline analogues with a norbornane skeleton, namely methyl (1S,2S,3R,4R)‐2‐benzamido‐3‐(1,2‐dihydroxyethyl)bicyclo[2.2.1]heptane‐2‐carboxylate, C18H23NO5, and methyl (1R,2S,3R,4S)‐2‐benzamido‐3‐(1,2‐dihydroxyethyl)bicyclo[2.2.1]heptane‐2‐carboxylate, C18H23NO5, exhibit a conformation in the helical region of the ?,ψ map but their handedness is opposite. In both cases, the torsion angles (χ1,1) giving the relative orientation of the 1,2‐dihydroxyethyl group of the amino acid side chain and the benzamide group of the peptide chain indicate that these groups adopt a nearly eclipsed conformation. Both compounds show a complex hydrogen‐bonding pattern. 相似文献
15.
Hugh W. Thompson Roger A. Lalancette 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):841-843
In the the title compound, 1,7‐dimethyl‐8‐oxo‐4bα,7α‐gibba‐1,3,4a(10a)‐triene‐10β‐carboxylic acid monohydrate, C18H20O3·H2O, the water of hydration accepts a hydrogen bond from the carboxyl and donates hydrogen bonds to the carboxyl carbonyl and the ketone in two different screw‐related neighbors, which are mutually translational, yielding a complex three‐dimensional hydrogen‐bonding array. 相似文献
16.
Montserrat Alfonso Yi Wang Helen Stoeckli-Evans 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(10):1184-1188
5,6-Bis(2-pyridyl)pyrazine-2,3-dicarboxylic acid exists as an inner-salt zwitterion, 3-carboxy-5-(2-pyridinio)-6-(2-pyridyl)pyrazine-2-carboxylate, (Ia), C16H10N4O4. The adjacent pyridine and pyridinium rings are almost coplanar due to the presence of an intramolecular hydrogen bond involving the pyridine N atom and the NH H atom of the pyridinium group. In the crystal of (Ia), symmetry-related molecules are hydrogen bonded via the carboxylic acid OH group and one of the carboxylate O atoms to form a polymer, which exhibits a channel-type structure. In the HCl, HClO4 and HPF6 salts, 6-carboxy-5-carboxylatopyrazine-2,3-diyldi-2-pyridinium chloride 2.25-hydrate, (II), C16H11N4O4+·Cl−·2.25H2O, 6-carboxy-5-carboxylatopyrazine-2,3-diyldi-2-pyridinium perchlorate trihydrate, (IIIa), C16H11N4O4+·ClO4−·3H2O, and 6-carboxy-5-carboxylatopyrazine-2,3-diyldi-2-pyridinium hexafluorophosphate trihydrate, (IIIb), C16H11N4O4+·PF6−·3H2O, both pyridine rings are protonated. In the perchlorate form, and in the isomorphous hexafluorophosphate form, the molecule possesses C2 symmetry, with has a symmetrical intramolecular hydrogen bond involving the adjacent carboxylate and carboxylic acid substituents. In the crystals of the chloride and perchlorate (or hexafluorophosphate) salts, hydrogen-bonded polymers are formed which are three-dimensional and one-dimensional, respectively. 相似文献
17.
Setsuo Kashino Takeo Fukunaga Hironobu Izutsu Shiho Miyashita 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):627-631
2‐Pyridone (2‐oxopyrimidine) forms hydrogen‐bonded complexes with dicarboxylic acids, the molar ratio of 2‐pyridone/dicarboxylic acid being 2:1 for the complexes with oxalic acid (ethanedioic acid), 2C5H5NO·C2H2O4, (I), and trans‐β‐hydromuconic acid (trans‐hex‐3‐enedioic acid), 2C5H5NO·C6H8O4, (II), and 1:1 for the complexes with trans‐glutaconic acid (trans‐pent‐2‐enedioic acid), C5H5NO·C5H6O4, (III), and l ‐tartaric acid (l ‐2,3‐dihydroxybutanedioic acid), C5H5NO·C4H6O6·H2O, (IV). Common features in the hydrogen‐bonding patterns were found for the centrosymmetric and non‐centrosymmetric acids, respectively. The 2‐pyridone molecule takes the lactam form in these crystals. 相似文献
18.
Ponraj Prabakaran Jebamony Justin Robert Packianathan Thomas Muthiah Gabriele Bocelli Lara Righi 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):459-461
In the title cocrystal, trimethoprim maleate [2,4‐diamino‐5‐(3,4,5‐trimethoxybenzyl)pyrimidin‐1‐ium maleate], C14H19N4O3+·C4H3O4?, the trimethoprim molecule is protonated at N1. The carboxyl group of the maleate ion makes a specific double hydrogen bond of type N—H?O with the 2‐amino group and the protonated N1 atom of the trimethoprim cation which is similar to the carboxylate–trimethoprim cation interaction observed in the complex of dihydrofolate reductase with trimethoprim. The pyrimidine moieties of trimethoprim cations are centrosymmetrically paired through a pair of N—H?N hydrogen bonds involving the 4‐amino group and the pyridinium N3 atom of a symmetry‐related molecule. One of the O atoms at the maleate carboxylate group bridges the 2‐amino and 4‐amino groups on either side of the paired trimethoprim cations. The other O atom of the carboxylate group forms an intramolecular O—H?O hydrogen bond with the carboxyl group. These characteristic hydrogen bonds result in infinite two‐dimensional aggregation of rings into a supramolecular ladder, which is further crosslinked through weak C—H?O interactions with methoxy groups of neighbouring trimethoprim molecules to form a layered structure. 相似文献
19.
Anthony Linden Miyase G. Gündüz Rahime imek Cihat afak 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):o227-o230
A mixture of the RR/SS and RS/SR diastereoisomeric pairs of methyl 4‐(2,4‐dichlorophenyl)‐2,7‐dimethyl‐5‐oxo‐1,4,5,6,7,8‐hexahydroquinoline‐3‐carboxylate, C19H19Cl2NO3, forms cocrystals in which there is one unique molecule in the asymmetric unit, but the molecule displays disorder in the region of the 7‐position of the quinoline ring system as a result of the random occurrence of the diastereoisomers at the same crystallographic site. A similar arrangement exists in the monohydrate cocrystals that form from a mixture of the RR/SS and RS/SR diastereoisomeric pairs of methyl 4‐(2,4‐dichlorophenyl)‐2‐methyl‐7‐phenyl‐5‐oxo‐1,4,5,6,7,8‐hexahydroquinoline‐3‐carboxylate monohydrate, C24H21Cl2NO3·H2O. These compounds belong to a class of 1,4‐dihydropyridines whose members have calcium modulatory properties. The 1,4‐dihydropyridine rings have the usual shallow boat conformation. In each structure, the 2,4‐dichlorophenyl ring is oriented such that the 2‐chloro substituent is in a synperiplanar orientation with respect to the 1,4‐dihydropyridine ring plane. In each crystal structure, the molecules are linked into chains by N—H⋯O hydrogen‐bonding interactions. 相似文献
20.
Jian Zhang Zhao‐Ji Li Yi‐Hang Wen Yao Kang Ye‐Yan Qin Yuan‐Gen Yao 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(8):m389-m391
The title compound, [Cd(C6H4NO2)2(H2O)2]n, forms a one‐dimensional chain structure based on a Cd atom with approximate pentagonal bipyramidal coordination geometry and two nicotinate ligands in different coordination modes. One acts as a tridentate ligand, chelating one Cd atom through the carboxylate group while simultaneously binding to a second symmetry‐related Cd atom through the pyridine N atom; the other acts only as a bidentate ligand through its carboxylate group. Hydrogen bonds utilizing the coordinated water molecules, uncoordinated nitrogen and carboxylate O atoms as acceptors link the chains. 相似文献