首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 437 毫秒
1.
Ga(IO3)3 crystallizes in the space group P63, with the Ga atom at a site with imposed threefold symmetry. The crystal structure consists of slightly distorted GaO6 octa­hedra that are bridged by I atoms of IO3 groups, giving rise to a three‐dimensional polar network. The framework contains unoccupied hexa­gonal channels running parallel to the hexa­gonal [001] direction. The iodate groups have their stereochemically active non‐bonded electron pairs pointing in the same direction along [001], which creates the polarity in the structure. The I—O bond distances and O—I—O angles are normal, being in the ranges 1.783 (3)–1.847 (2) Å and 94.68 (11)–99.61 (12)°, respectively.  相似文献   

2.
The asymmetric unit of the title compound, [Pb2(C8H3IO4)2(CH4O)]n, contains two PbII atoms, two 5‐iodoisophthalate (5‐IIP2−) ligands and one coordinated methanol molecule. One Pb atom is eight‐coordinated, surrounded by seven carboxylate O atoms from five 5‐IIP2− ligands and one O atom from the terminal methanol ligand. The other Pb atom is seven‐coordinated in a hemidirected geometry, surrounded by seven carboxylate O atoms from five 5‐IIP2− ligands. Both Pb atoms are connected by carboxylate groups to form a one‐dimensional infinite rod along the a axis; neighbouring rods are further linked by the aromatic rings of 5‐IIP2− to generate the final three‐dimensional structure with channels in the a direction. An O—H...O hydrogen bond between the methanol ligand and one of the carboxylate groups of a 5‐IIP2− ligand stablizes the three‐dimensional framework. Interestingly, a centrosymmetric rhombus‐shaped I4 unit is formed by four 5‐IIP2− ligands, with I...I distances of 3.8841 (8) and 3.9204 (8) Å.  相似文献   

3.
The title 3‐nitrophthalate–calcium coordination polymer, {[Ca(C8H3NO6)(H2O)2]·H2O}n, crystallizes as a one‐dimensional framework. The CaII centre has a distorted pentagonal–bipyramidal geometry, being seven‐coordinated by five O atoms from three different 3‐nitrophthalate groups and by two water molecules, resulting in a one‐dimensional zigzag chain along the a‐axis direction by the interconnection of the four O atoms from the two carboxylate groups. There is a D3 water cluster composed of the coordinated and the solvent water molecules within such chains. Adjacent chains are aggregated into two‐dimensional layers via hydrogen bonds in the c‐axis direction. The whole three‐dimensional structure is further stabilized by weak O—H...O hydrogen bonds between the O atoms of the nitro group and the water molecules.  相似文献   

4.
Solvent‐free (2S)‐methyl 2‐ammonio‐3‐(4‐hydroxy­phenyl)­propionate chloride, C10H14NO3+·Cl, (I), and its methanol solvate, C10H14NO3+·Cl·CH3OH, (II), are obtained from different solvents: crystallization from ethanol or propan‐2‐ol gives the same solvent‐free crystals of (I) in both cases, while crystals of (II) were obtained by crystallization from methanol. The structure of (I) is characterized by the presence of two‐dimensional layers linked together by N—H⋯Cl and O—H⋯Cl hydrogen bonds and also by C—H⋯O contacts. Incorporation of the methanol solvent mol­ecule in (II) introduces additional O—H⋯O hydrogen bonds linking the two‐dimensional layers, resulting in the formation of a three‐dimensional network.  相似文献   

5.
The title compounds, dimethylammonium 2‐{4‐[1‐(4‐carboxymethoxyphenyl)‐1‐methylethyl]phenoxy}acetate, C2H8N+·C19H19O6, (I), and 2,2′‐[isopropylidenebis(p‐phenyleneoxy)]diacetic acid–4,4′‐bipyridine (1/1), C19H20O6·C10H8N2, (II), are 1:1 adducts of 2,2′‐[isopropylidenebis(p‐phenyleneoxy)]diacetic acid (H2L) with dimethylammonium or 4,4′‐bipyridine. The component ions in (I) are linked by N—H...O, O—H...O and C—H...O hydrogen bonds into continuous two‐dimensional layers parallel to the (001) plane. Adjacent layers are stacked via C—H...O hydrogen bonds into a three‐dimensional network with an –ABAB– alternation of the two‐dimensional layers. In (II), two H2L molecules, one bipy molecule and two half bipy molecules are linked by O—H...N hydrogen bonds into one‐dimensional chains and rectanglar‐shaped rings. They are assembled viaπ–π stacking interactions and C—H...O hydrogen bonds into an intriguing zero‐dimensional plus one‐dimensional poly(pseudo)rotaxane motif.  相似文献   

6.
Both the 1:1 and 2:1 molecular adducts of 4‐methylimidazole (4‐MeIm) and terephthalic acid (H2TPA) are organic salts, viz. C4H7N2+·C8H5O4, (I), and 2C4H7N2+·C8H4O42−, (II), respectively. The component ions in (I) are linked by N—H...O and O—H...O hydrogen bonds into continuous two‐dimensional layers built from R64(32) hydrogen‐bond motifs running parallel to the (100) plane. These adjacent two‐dimensional layers are in turn linked by a combination of C—H...O, C—H...π and π–π interactions into a three‐dimensional network. In the crystal structure of (II), with the anion located on an inversion centre, only N—H...O hydrogen bonds result in two‐dimensional layers built from R88(42) hydrogen‐bond motifs running parallel to the (102) plane. Being similar to those in (I), these layers are also linked by means of C—H...O, C—H...π and π–π interactions, forming a three‐dimensional network. This study indicates that, on occasion, a change of the reactant concentration can exert a pivotal influence on the construction of supramolecular structures based on hydrogen bonds.  相似文献   

7.
The structures of ammonium 3,5‐dinitrobenzoate, NH4+·C7H3N2O6, (I), ammonium 4‐nitrobenzoate dihydrate, NH4+·C7H4NO4·2H2O, (II), and ammonium 2,4‐dichlorobenzoate hemihydrate, NH4+·C7H3Cl2O2·0.5H2O, (III), have been determined and their hydrogen‐bonded structures are described. All three salts form hydrogen‐bonded polymeric structures, viz. three‐dimensional in (I) and two‐dimensional in (II) and (III). With (I), a primary cation–anion cyclic association is formed [graph set R43(10)] through N—H...O hydrogen bonds, involving a carboxylate group with both O atoms contributing to the hydrogen bonds (denoted O,O′‐carboxylate) on one side and a carboxylate group with one O atom involved in two hydrogen bonds (denoted O‐carboxylate) on the other. Structure extension involves N—H...O hydrogen bonds to both carboxylate and nitro O‐atom acceptors. With structure (II), the primary inter‐species interactions and structure extension into layers lying parallel to (001) are through conjoined cyclic hydrogen‐bonding motifs, viz.R43(10) (one cation, an O,O′‐carboxylate group and two water molecules) and centrosymmetric R42(8) (two cations and two water molecules). The structure of (III) also has conjoined R43(10) and centrosymmetric R42(8) motifs in the layered structure but these differ in that the first motif involves one cation, an O,O′‐carboxylate group, an O‐carboxylate group and one water molecule, and the second motif involves two cations and two O‐carboxylate groups. The layers lie parallel to (100). The structures of salt hydrates (II) and (III), displaying two‐dimensional layered arrays through conjoined hydrogen‐bonded nets, provide further illustration of a previously indicated trend among ammonium salts of carboxylic acids, but the anhydrous three‐dimensional structure of (I) is inconsistent with that trend.  相似文献   

8.
In the title complex, {[Cd2(C8H3NO6)2(C4H10N2)(H2O)4]·2H2O}n, the CdII atoms show distorted octahedral coordination. The two carboxylate groups of the dianionic 2‐nitroterephthalate ligand adopt monodentate and 1,2‐bridging modes. The piperazine molecule is in a chair conformation and lies on a crystallographic inversion centre. The CdII atoms are connected via three O atoms from two carboxylate groups and two N atoms from piperazine molecules to form a two‐dimensional macro‐ring layer structure. These layers are further aggregated to form a three‐dimensional structure via rich intra‐ and interlayer hydrogen‐bonding networks. This study illustrates that, by using the labile CdII salt and a combination of 2‐nitroterephthalate and piperazine as ligands, it is possible to generate interesting metal–organic frameworks with rich intra‐ and interlayer O—H...O hydrogen‐bonding networks.  相似文献   

9.
The structures of two hydrated salts of 4‐aminophenylarsonic acid (p‐arsanilic acid), namely ammonium 4‐aminophenylarsonate monohydrate, NH4+·C6H7AsNO3·H2O, (I), and the one‐dimensional coordination polymer catena‐poly[[(4‐aminophenylarsonato‐κO)diaquasodium]‐μ‐aqua], [Na(C6H7AsNO3)(H2O)3]n, (II), have been determined. In the structure of the ammonium salt, (I), the ammonium cations, arsonate anions and water molecules interact through inter‐species N—H...O and arsonate and water O—H...O hydrogen bonds, giving the common two‐dimensional layers lying parallel to (010). These layers are extended into three dimensions through bridging hydrogen‐bonding interactions involving the para‐amine group acting both as a donor and an acceptor. In the structure of the sodium salt, (II), the Na+ cation is coordinated by five O‐atom donors, one from a single monodentate arsonate ligand, two from monodentate water molecules and two from bridging water molecules, giving a very distorted square‐pyramidal coordination environment. The water bridges generate one‐dimensional chains extending along c and extensive interchain O—H...O and N—H...O hydrogen‐bonding interactions link these chains, giving an overall three‐dimensional structure. The two structures reported here are the first reported examples of salts of p‐arsanilic acid.  相似文献   

10.
The title compound, [Cu(C9H13N5O2)(CH4O)](NO3)2, consists of square‐planar cationic complex units where the CuII centre is coordinated by an N,N′,O‐tridentate pyridoxal–aminoguanidine Schiff base adduct and a methanol molecule. The tridentate ligand is a zwitterion exhibiting an almost planar conformation. The dihedral angles between the mean planes of the pyridoxal ring and the six‐ and five‐membered chelate rings are all less than 2.0°. The charge on the complex cation is neutralized by two nitrate counter‐ions. Extensive N—H...O and C—H...O hydrogen bonding connects these ionic species and leads to the formation of layers. The pyridoxal hydroxy groups are the only fragments that deviate significantly from the flat layer structure; these groups are involved in O—H...O hydrogen bonding, connecting the layers into a three‐dimensional crystal structure.  相似文献   

11.
In the title polymeric heterometallic compound, {[Cu3Gd(C6H4NO2)3Cl3(H2O)2]·0.5H2O}n, comprising copper(I) and gadolinium(III) cations bridged by nicotinate (nic) ligands and chloride anions, the GdIII centers display a bicapped trigonal prismatic geometry, defined by six carboxylate O atoms and two water molecules. For copper(I), one Cu center is three‐coordinated by three chloride ions and displays a trigonal–planar geometry; the other two Cu centers are four‐coordinated and display a very distorted tetrahedral geometry. The chloride anions act in μ2‐ and μ3‐bridging modes, linking the CuI ions into an infinite chain. The nic ligand exhibits a tridentate coordination mode, with the carboxylate O atoms linking to two GdIII ions and the N atom linking to one CuI ion. Thus, a novel three‐dimensional heterometallic coordination polymer is constructed from Gd–carboxylate subunits and Cu—Cl chains. In addition, intra‐ and intermolecular O—H...O and O—H...Cl hydrogen bonds are also observed within the three‐dimensional structure. Topologically, the framework represents an unusual 3,6‐connected (4.82)3(410.65) net.  相似文献   

12.
The 1:1 proton‐transfer compounds of l ‐tartaric acid with 3‐aminopyridine [3‐aminopyridinium hydrogen (2R,3R)‐tartrate dihydrate, C5H7N2+·C4H5O6·2H2O, (I)], pyridine‐3‐carboxylic acid (nicotinic acid) [anhydrous 3‐carboxypyridinium hydrogen (2R,3R)‐tartrate, C6H6NO2+·C4H5O6, (II)] and pyridine‐2‐carboxylic acid [2‐carboxypyridinium hydrogen (2R,3R)‐tartrate monohydrate, C6H6NO2+·C4H5O6·H2O, (III)] have been determined. In (I) and (II), there is a direct pyridinium–carboxyl N+—H...O hydrogen‐bonding interaction, four‐centred in (II), giving conjoint cyclic R12(5) associations. In contrast, the N—H...O association in (III) is with a water O‐atom acceptor, which provides links to separate tartrate anions through Ohydroxy acceptors. All three compounds have the head‐to‐tail C(7) hydrogen‐bonded chain substructures commonly associated with 1:1 proton‐transfer hydrogen tartrate salts. These chains are extended into two‐dimensional sheets which, in hydrates (I) and (III) additionally involve the solvent water molecules. Three‐dimensional hydrogen‐bonded structures are generated via crosslinking through the associative functional groups of the substituted pyridinium cations. In the sheet struture of (I), both water molecules act as donors and acceptors in interactions with separate carboxyl and hydroxy O‐atom acceptors of the primary tartrate chains, closing conjoint cyclic R44(8), R34(11) and R33(12) associations. Also, in (II) and (III) there are strong cation carboxyl–carboxyl O—H...O hydrogen bonds [O...O = 2.5387 (17) Å in (II) and 2.441 (3) Å in (III)], which in (II) form part of a cyclic R22(6) inter‐sheet association. This series of heteroaromatic Lewis base–hydrogen l ‐tartrate salts provides further examples of molecular assembly facilitated by the presence of the classical two‐dimensional hydrogen‐bonded hydrogen tartrate or hydrogen tartrate–water sheet substructures which are expanded into three‐dimensional frameworks via peripheral cation bifunctional substituent‐group crosslinking interactions.  相似文献   

13.
A polydentate ligand bridged by a fluorene group, namely 9,9‐bis(2‐hydroxyethyl)‐2,7‐bis(pyridin‐4‐yl)fluorene (L), has been prepared under solvothermal conditions in acetonitrile. Crystals of the three‐dimensional metal–organic framework (MOF) poly[[[μ3‐9,9‐bis(2‐hydroxyethyl)‐2,7‐bis(pyridin‐4‐yl)fluorene‐κ3N:N′:O]bis(methanol‐κO)(μ‐sulfato‐κ2O:O′)nickel(II)] methanol disolvate], {[Ni(SO4)(C27H24N2O2)(CH3OH)]·2CH3OH}n, (I), were obtained by the solvothermal reaction of L and NiSO4 in methanol. The ligand L forms a two‐dimensional network in the crystallographic bc plane via two groups of O—H…N hydrogen bonds and neighbouring two‐dimensional planes are completely parallel and stack to form a three‐dimensional structure. In (I), the NiII ions are linked by sulfate ions through Ni—O bonds to form inorganic chains and these Ni‐containing chains are linked into a three‐dimensional framework via Ni—O and Ni—N bonds involving the polydentate ligand L. With one of the hydroxy groups of L coordinating to the NiII atom, the torsion angle of the hydroxyethyl group changes from that of the uncoordinated molecule. In addition, the adsorption properties of (I) with carbon dioxide were investigated.  相似文献   

14.
The title complex, [Cd2(C2H2N3)(OH)(SO4)]n, is a three‐dimensional metal–organic framework consisting of pseudo‐cubane‐like tetranuclear cadmium clusters, which are formed by four CdII atoms, two sulfate groups and two hydroxide groups. The tetranuclear cadmium clusters are connected into a layered substructure by Cd—O bonds and adjacent layers are linked by triazolate ligands into a three‐dimensional network. A photoluminescent study revealed that the complex exhibits a strong emission in the visible region which probably originates from a π–π* transition.  相似文献   

15.
Crystal Structure, Infrared and Raman Spectra of Copper Trihydrogenperiodate Monohydrate, CuH3IO6 · H2O The hitherto unknown compound CuH3IO6 · H2O was studied by X‐ray, IR‐ and Raman spectroscopic methods. The crystal structure was determined by X‐ray single‐crystal studies (space group P212121, Z = 4, a = 532.60(10), b = 624.00(10), c = 1570.8(3) pm, R1 = 1.85%, 1559 unique reflections (I > 2σ(I))). Isolated, meridionally configurated H3IO62– ions are coordinated to the copper ions forming double‐ropes in [100]. These ropes are connected in [010] and [001] by hydrogen bonds. The copper ions possess a square pyramidal co‐ordination with the hydrate H2O on top. The infrared and Raman spectra as well as group theoretical treatment are presented and discussed with respect to the strength of the hydrogen bonds and the co‐ordination of the CuO5(+1) polyhedra and the H3IO62– ions at the C1 lattice sites. The hydrogen bonds of the H2O molecules and H3IO62– ions (HO–H…O–IO5H3 and H2IO5O–H…O–IO5H3) greatly differ in strength, as shown from both the respective O…O distances: 282.6 and 298.6 pm (H2O), and 258.8, 259.7, and 270.9 pm (H3IO62–) and the OD stretching modes of isotopically dilute samples: 2498 and 2564 cm–1 (90 K) (HDO), and 1786, 2024, and 2188 cm–1 (H2DIO62–). The IO stretching modes of the H3IO62– ions (696–788 cm–1 and 555–658 cm–1, 295 K) display the different strength of the respective I–O and I–O(H) bonds (rI–O: 181.1–188.3 pm and 189.2–194.5 pm).  相似文献   

16.
Crystals of bis(2‐ethyl‐3‐hydroxy‐6‐methylpyridinium) succinate–succinic acid (1/1), C8H12NO+·0.5C4H4O42−·0.5C4H6O4, (I), and 2‐ethyl‐3‐hydroxy‐6‐methylpyridinium hydrogen succinate, C8H12NO+·C4H5O4, (II), were obtained by reaction of 2‐ethyl‐6‐methylpyridin‐3‐ol with succinic acid. The succinate anion and succinic acid molecule in (I) are located about centres of inversion. Intermolecular O—H...O, N—H...O and C—H...O hydrogen bonds are responsible for the formation of a three‐dimensional network in the crystal structure of (I) and a two‐dimensional network in the crystal structure of (II). Both structures are additionally stabilized by π–π interactions between symmetry‐related pyridine rings, forming a rod‐like cationic arrangement for (I) and cationic dimers for (II).  相似文献   

17.
A cyano‐bridged bimetallic 4f–3d complex, tri­aqua‐1κ3O‐μ‐cyano‐1:2κ2N:C‐penta­cyano‐2κ5C‐tetrakis(2‐pyrrolidone‐1κO)­chromium(III)­dysprosium(III) dihydrate, [CrDy(C4H7NO)4(CN)6(H2O)3]·2H2O, has been prepared and characterized by X‐ray crystallographic analysis. The structure consists of a neutral cyano‐bridged Dy–Cr dimer. A hydrogen‐bonded three‐dimensional architecture is formed through N—H?O, O—H?N and O—H?O hydrogen bonds.  相似文献   

18.
The interaction of the antimigraine pharmaceutical agent frovatriptan with acetic acid and succinic acid yields the salts (±)‐6‐carbamoyl‐N‐methyl‐2,3,4,9‐tetrahydro‐1H‐carbazol‐3‐aminium acetate, C14H18N3O+·C2H3O2, (I), (R)‐(+)‐6‐carbamoyl‐N‐methyl‐2,3,4,9‐tetrahydro‐1H‐carbazol‐3‐aminium 3‐carboxypropanoate monohydrate, C14H18N3O+·C4H5O4·H2O, (II), and bis[(R)‐(+)‐6‐carbamoyl‐N‐methyl‐2,3,4,9‐tetrahydro‐1H‐carbazol‐3‐aminium] succinate trihydrate, 2C14H18N3O+·C4H4O42−·3H2O, (III). The methylazaniumyl substitutent is oriented differently in all three structures. Additionally, the amide group in (I) is in a different orientation. All the salts form three‐dimensional hydrogen‐bonded structures. In (I), the cations form head‐to‐head hydrogen‐bonded amide–amide catemers through N—H...O interactions, while in (II) and (III) the cations form head‐to‐head amide–amide dimers. The cation catemers in (I) are extended into a three‐dimensional network through further interactions with acetate anion acceptors. The presence of succinate anions and water molecules in (II) and (III) primarily governs the three‐dimensional network through water‐bridged cation–anion associations via O—H...O and N—H...O hydrogen bonds. The structures reported here shed some light on the possible mode of noncovalent interactions in the aggregation and interaction patterns of drug molecule adducts.  相似文献   

19.
The structures of two ammonium salts of 3‐carboxy‐4‐hydroxybenzenesulfonic acid (5‐sulfosalicylic acid, 5‐SSA) have been determined at 200 K. In the 1:1 hydrated salt, ammonium 3‐carboxy‐4‐hydroxybenzenesulfonate monohydrate, NH4+·C7H5O6S·H2O, (I), the 5‐SSA monoanions give two types of head‐to‐tail laterally linked cyclic hydrogen‐bonding associations, both with graph‐set R44(20). The first involves both carboxylic acid O—H...Owater and water O—H...Osulfonate hydrogen bonds at one end, and ammonium N—H...Osulfonate and N—H...Ocarboxy hydrogen bonds at the other. The second association is centrosymmetric, with end linkages through water O—H...Osulfonate hydrogen bonds. These conjoined units form stacks down c and are extended into a three‐dimensional framework structure through N—H...O and water O—H...O hydrogen bonds to sulfonate O‐atom acceptors. Anhydrous triammonium 3‐carboxy‐4‐hydroxybenzenesulfonate 3‐carboxylato‐4‐hydroxybenzenesulfonate, 3NH4+·C7H4O6S2−·C7H5O6S, (II), is unusual, having both dianionic 5‐SSA2− and monoanionic 5‐SSA species. These are linked by a carboxylic acid O—H...O hydrogen bond and, together with the three ammonium cations (two on general sites and the third comprising two independent half‐cations lying on crystallographic twofold rotation axes), give a pseudo‐centrosymmetric asymmetric unit. Cation–anion hydrogen bonding within this layered unit involves a cyclic R33(8) association which, together with extensive peripheral N—H...O hydrogen bonding involving both sulfonate and carboxy/carboxylate acceptors, gives a three‐dimensional framework structure. This work further demonstrates the utility of the 5‐SSA monoanion for the generation of stable hydrogen‐bonded crystalline materials, and provides the structure of a dianionic 5‐SSA2− species of which there are only a few examples in the crystallographic literature.  相似文献   

20.
The title compounds, C8H11NO, (I), and 2C8H12NO+·C4H4O42−, (II), both crystallize in the monoclinic space group P21/c. In the crystal structure of (I), intermolecular O—H...N hydrogen bonds combine the molecules into polymeric chains extending along the c axis. The chains are linked by C—H...π interactions between the methylene H atoms and the pyridine rings into polymeric layers parallel to the ac plane. In the crystal structure of (II), the succinate anion lies on an inversion centre. Its carboxylate groups interact with the 2‐ethyl‐3‐hydroxy‐6‐methylpyridinium cations via intermolecular N—H...O hydrogen bonds with the pyridine ring H atoms and O—H...O hydrogen bonds with the hydroxy H atoms to form polymeric chains, which extend along the [01] direction and comprise R44(18) hydrogen‐bonded ring motifs. These chains are linked to form a three‐dimensional network through nonclassical C—H...O hydrogen bonds between the pyridine ring H atoms and the hydroxy‐group O atoms of neighbouring cations. π–π interactions between the pyridine rings and C—H...π interactions between the methylene H atoms of the succinate anion and the pyridine rings are also present in this network.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号