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1.
The complexes [2‐(1H‐imidazol‐4‐yl‐κN3)ethylamine‐κN]bis(tri‐tert‐butoxysilanethiolato‐κS)cobalt(II), [Co(C12H27O3SSi)2(C5H9N3)], and [2‐(1H‐imidazol‐4‐yl‐κN3)ethylamine‐κN]bis(tri‐tert‐butoxysilanethiolato‐κS)zinc(II), [Zn(C12H27O3SSi)2(C5H9N3)], are isomorphous. The central ZnII/CoII ions are surrounded by two S atoms from the tri‐tert‐butoxysilanethiolate ligand and by two N atoms from the chelating histamine ligand in a distorted tetrahedral geometry, with two intramolecular N—H...O hydrogen‐bonding interactions between the histamine NH2 groups and tert‐butoxy O atoms. Molecules of the complexes are joined into dimers via two intermolecular bifurcated N—H...(S,O) hydrogen bonds. The ZnII atom in [(1H‐imidazol‐4‐yl‐κN3)methanol]bis(tri‐tert‐butoxysilanethiolato‐κ2O,S)zinc(II), [Zn(C12H27O3SSi)2(C4H6N2O)], is five‐coordinated by two O and two S atoms from the O,S‐chelating silanethiolate ligand and by one N atom from (1H‐imidazol‐4‐yl)methanol; the hydroxy group forms an intramolecular hydrogen bond with sulfur. Molecules of this complex pack as zigzag chains linked by N—H...O hydrogen bonds. These structures provide reference details for cysteine‐ and histidine‐ligated metal centers in proteins.  相似文献   

2.
The title complexes, catena‐poly[[aqua(1,10‐phenanthroline‐κ2N,N′)­cobalt(II)]‐μ‐benzene‐1,4‐di­carboxyl­ato‐κ2O1:O4], [Co(C8H4O4)(C12H8N2)(H2O)], (I), and catena‐poly[[[(di‐2‐pyridyl‐κN‐amine)copper(II)]‐μ‐benzene‐1,4‐di­carboxyl­ato‐κ4O1,O1′:O4,O4′] hydrate], [Cu(C8H4O4)(C10H9N3)]·H2O, (II), take the form of zigzag chains, with the 1,4‐benzene­di­carboxyl­ate ion acting as an amphimonodentate ligand in (I) and a bis‐bidentate ligand in (II). The CoII ion in (I) is five‐coordinate and has a distorted trigonal–bipyramidal geometry. The CuII ion in (II) is in a very distorted octahedral 4+2 environment, with the octahedron elongated along the trans O—Cu—O bonds and with a trans O—Cu—O angle of only 137.22 (8)°.  相似文献   

3.
The calcium salts Ca2P2O6 · 2H2O ( 1 ) and [Ca(H2O)3(H2P2O6)] · 0.5(C12H24O6) · H2O ( 2 ) were prepared and structurally characterized by single‐crystal X‐ray diffraction. Compound 1 crystallizes in the orthorhombic space group Pbca and compound 2 in the monoclinic space group P21/n. The crystal structure of compound 1 consists of chains of edge‐sharing [CaO7] polyhedra linked by hypodiphosphate(IV) anions to form a three‐dimensional network. The crystal structure of compound 2 consists of alternated layers of crown ether and water molecules and respective ionic units. Within the layers of ionic units the Ca2+ cations are octahedrally coordinated by three monodentate dihydrogenhypodiphosphate(IV) anions and three water molecules. The IR/Raman spectra of the title compounds were recorded and interpreted, especially with respect to the [P2O6]4– and [H2P2O6]2– groups. The phase purity of 2 was verified by powder diffraction measurements.  相似文献   

4.
The present paper reports the structures of bis(adeninium) zoledronate tetrahydrate {systematic name: bis(6‐amino‐7H‐purin‐1‐ium) hydrogen [1‐hydroxy‐2‐(1H‐imidazol‐3‐ium‐1‐yl)‐1‐phosphonatoethyl]phosphonate tetrahydrate}, 2C5H6N5+·C5H8N2O7P22−·4H2O, (I), and bis(adeninium) zoledronate hexahydrate {systematic name: a 1:1 cocrystal of bis(6‐amino‐7H‐purin‐1‐ium) hydrogen [1‐hydroxy‐2‐(1H‐imidazol‐3‐ium‐1‐yl)‐1‐phosphonatoethyl]phosphonate hexahydrate and 6‐amino‐7H‐purin‐1‐ium 6‐amino‐7H‐purine dihydrogen [1‐hydroxy‐2‐(1H‐imidazol‐3‐ium‐1‐yl)ethane‐1,1‐diyl]diphosphonate hexahydrate}, 2C5H6N5+·C5H8N2O7P22−·6H2O, (II). One of the adenine molecules and one of the phosphonate groups of the zoledronate anion of (II) are protonated on a 50% basis. The zoledronate group displays its usual zwitterionic character, with a protonated imidazole ring; however, the ionization state of the phosphonate groups of the anion for (I) and (II) are different. In (I), the anion has both singly and doubly deprotonated phosphonate groups, while in (II), it has one singly deprotonated phosphonate group and a partially deprotonated phosphonate group. In (I), the cations form an R22(10) base pair, while in (II), they form R22(8) and R22(10) base pairs. Two water molecules in (I) and five water molecules in (II) are involved in water–water interactions. The presence of an additional two water molecules in the structure of (II) might influence the different ionization state of the anion as well as the different packing mode compared to (I).  相似文献   

5.
In the title cadmium(II) complex, [Cd(C8H4O5)(C14H14N4)(H2O)]n, the 5‐hydroxybenzene‐1,3‐dicarboxylate (5‐OH‐1,3‐bdc) and 1,4‐bis(imidazol‐1‐ylmethyl)benzene (1,4,‐bix) ligands bridge water‐coordinated CdII atoms to generate a three‐dimensional network. Two carboxylate groups from different ligands function as O,O′‐chelates, while two imidazole N atoms from different ligands coordinate in a monodentate fashion, and one water molecule completes the seven‐coordinate pentagonal bipyramid around the CdII atom, in which the N atoms occupy the axial sites and the O atoms occupy the equatorial sites. The overall architecture is a twofold interpenetrated CdSO4‐type framework. The two crystallographically equivalent frameworks are linked by O—H...O hydrogen bonds between the water, hydroxy and carboxylate groups.  相似文献   

6.
The scandium(III) cations in the structures of pentaaqua(biuret‐κ2O,O′)scandium(III) trichloride monohydrate, [Sc(C2H5N3O2)(H2O)5]Cl3·H2O, (I), and tetrakis(biuret‐κ2O,O′)scandium(III) trinitrate, [Sc(C2H5N3O2)4](NO3)3, (II), are found to adopt very different coordinations with the same biuret ligand. The roles of hydrogen bonding and the counter‐ion in the establishment of the structures are described. In (I), the Sc3+ cation adopts a fairly regular pentagonal bipyramidal coordination geometry arising from one O,O′‐bidentate biuret molecule and five water molecules. A dense network of N—H...Cl, O—H...O and O—H...Cl hydrogen bonds help to establish the packing, resulting in dimeric associations of two cations and two water molecules. In (II), the Sc3+ cation (site symmetry 2) adopts a slightly squashed square‐antiprismatic geometry arising from four O,O′‐bidentate biuret molecules. A network of N—H...O hydrogen bonds help to establish the packing, which features [010] chains of cations. One of the nitrate ions is disordered about an inversion centre. Both structures form three‐dimensional hydrogen‐bond networks.  相似文献   

7.
The crystal and molecular structure of dipotassium di‐μ‐oxo‐bis[aqua(oxalato‐O1,O2)oxomolybdenum(III)] trihydrate, K2­[Mo2O4(C2O4)2(H2O)2]·3H2O, has been determined from X‐ray diffraction data. In the dimeric anion, which has approximate twofold symmetry, each Mo atom is in a distorted octahedral coordination, being bonded to one terminal oxo‐O atom, two bridging O atoms, two O atoms from the oxalato ligand and one from the water mol­ecule. Bond lengths trans to the multiple‐bonded terminal oxo ligand are larger than those in the cis position, confirming the trans influence as a generally valid rule.  相似文献   

8.
The water exchange reaction of [Be(H2O)2(1H‐imidazole‐4,5‐dicarboxylate)] and [Be(H2O)2(1H‐imidazol‐3‐ium‐4,5‐dicarboxylate)]+ in water was studied by DFT calculations (RB3LYP/6‐311+G**) and identified as an associative interchange mechanism. The activation barriers for [Be(H2O)2(1H‐imidazole‐4,5‐dicarboxylate)] (16.6 kcal/mol) and [Be(H2O)2(1H‐imidazol‐3‐ium‐4,5‐dicarboxylate)]+ (13.8 kcal/mol) are similar to the barrier for [Be(H2O)4)]2+ and independent of the overall charge. NICS calculations show no indication that the aromaticity of the imidazole ring is affected during the water exchange process.  相似文献   

9.
A new three‐dimensional interpenetrated CdII–organic framework based on 3,3′‐azodibenzoic acid [3,3′‐(diazenediyl)dibenzoic acid, H2azdc] and the auxiliary flexible ligand 1,4‐bis(1H‐imidazol‐1‐yl)butane (bimb), namely poly[[bis[μ2‐1,4‐bis(1H‐imidazol‐1‐yl)butane‐κ2N3:N3′][μ2‐3,3′‐(diazenediyl)dibenzoato‐κ2O:O′]cadmium(II)] monohydrate], {[Cd(C14H8N2O4)(C10H14N2)2]·H2O}n, (1), was obtained by a typical solution reaction in mixed solvents (water and N,N′‐dimethylformamide). Each CdII centre is six‐coordinated by two O atoms of bis‐monodentate bridging carboxylate groups from two azdc2− ligands and by four N atoms from four bimb ligands, forming an octahedral coordination environment. The CdII ions are connected by the bimb ligands, resulting in two‐dimensional (4,4) layers, which are further pillared by the azdc2− ligands, affording a threefold interpenetrated three‐dimensional α‐Po topological framework with the Schläfli symbol 41263. The thermal stability and solid‐state fluorescence properties of (1) have been investigated.  相似文献   

10.
In the crystal structure of the title compound, bis­(2‐amino­pyrimidine‐κN1)bis­[6‐meth­yl‐1,2,3‐oxathia­zin‐4(3H)‐one 2,2‐dioxide(1−)‐κ2N3,O4]copper(II), [Cu(C4H4NO4S)2(C4H5N3)2], the first mixed‐ligand complex of acesulfame, the CuII centre resides on a centre of symmetry and has an octa­hedral geometry that is distorted both by the presence of four‐membered chelate rings and by the Jahn–Teller effect. The equatorial plane is formed by the N atoms of two amino­pyrimidine (ampym) ligands and by the weakly basic carbonyl O atoms of the acesulfamate ligands, while the more basic deprotonated N atoms of these ligands are in the elongated axial positions with a strong misdirected valence. The crystal is stabilized by pyrimidine ring stacking and by inter­molecular hydrogen bonding involving the NH2 moiety of the ampym ligand and the carbon­yl O atom of the acesulfamate moiety.  相似文献   

11.
Rubidium chromium(III) dioxalate dihydrate [di­aqua­bis(μ‐oxalato)­chromium(III)­rubidium(I)], [RbCr(C2O4)2(H2O)2], (I), and dicaesium magnesium dioxalate tetrahydrate [tetra­aqua­bis(μ‐oxalato)­magnesium(II)­dicaesium(I)], [Cs2Mg(C2­O4)2(H2O)4], (II), have layered structures which are new among double‐metal oxalates. In (I), the Rb and Cr atoms lie on sites with imposed 2/m symmetry and the unique water molecule lies on a mirror plane; in (II), the Mg atom lies on a twofold axis. The two non‐equivalent Cr and Mg atoms both show octahedral coordination, with a mean Cr—O distance of 1.966 Å and a mean Mg—O distance of 2.066 Å. Dirubid­ium copper(II) dioxalate dihydrate [di­aqua­bis(μ‐oxalato)­copper(II)­dirubidium(I)], [Rb2Cu(C2O4)2(H2O)2], (III), is also layered and is isotypic with the previously described K2‐ and (NH4)2CuII(C2O4)2·2H2O compounds. The two non‐equivalent Cu atoms lie on inversion centres and are both (4+2)‐coordinated. Hydro­gen bonds are medium‐strong to weak in the three compounds. The oxalate groups are slightly non‐planar only in the Cs–Mg compound, (II), and are more distinctly non‐planar in the K–Cu compound, (III).  相似文献   

12.
The title compound, [CuBr(C6H7NO)2]Br·H2O, is an ionic mononuclear complex in which the [CuBr(C6H7NO)2]+ cation possesses distorted square‐pyramidal geometry. The CuII centre is coordinated by two neutral 2‐(pyridin‐2‐yl)methanol (2‐pyMeOH) ligands and a terminal bromide ligand. The 2‐pyMeOH ligands are coordinated in a bidentate chelating manner through the pyridine N and hydroxy O atoms, forming a five‐membered chelate ring with the CuII centre. The planes of the pyridine rings are twisted by 58.71 (14)° with respect to each other. The charge is balanced by a noncoordinating bromide anion which, together with a solvent water molecule, links the components through hydrogen bonds into infinite chains propagating along the a axis. The mononuclear cations appear to associate in pairs through weak interactions between the metal atom of one cation and the halogen atom of an adjacent cation.  相似文献   

13.
A new polymorph of a mononuclear nickel(II) acetate complex with 2‐(pyridin‐2‐yl)ethanol ligands, [Ni(CH3COO)2(C7H9NO)2], has been prepared and structurally characterized. Its molecular structure resembles the structures of two previously reported polymorphs in that the NiII atom is located on an inversion centre and is coordinated by pairs of acetate and 2‐(pyridin‐2‐yl)ethanol ligands. The acetate anions are coordinated in a monodentate manner, while the 2‐(pyridin‐2‐yl)ethanol ligands are coordinated in a bidentate chelating mode involving the endocyclic N atom and the hydroxy O atom of the ligand side chain. A strong bifurcated intramolecular hydrogen‐bond interaction was observed involving the hydroxy O atom as donor and both acetate O atoms as acceptors. No classical intermolecular hydrogen‐bond contacts were observed. However, the crystal packing is effected through π–π and C—H...π interactions, giving rise to a different packing arrangement. A brief comparison of the three polymorphic forms is presented.  相似文献   

14.
Two tricarbonyl complexes of rhenium(I) and manganese(I) coordinated by the ligand 2‐{[2‐(1H‐imidazol‐4‐yl)ethyl]iminomethyl}‐5‐methylphenolate are reported, viz. fac‐tricarbonyl(2‐{[2‐(1H‐imidazol‐4‐yl‐κN3)ethyl]iminomethyl‐κN}‐5‐methylphenolato‐κO)rhenium(I) methanol monosolvate, [Re(C16H14N3O4)(CO)3]·CH3OH, (I), and fac‐tricarbonyl(2‐{[2‐(1H‐imidazol‐4‐yl‐κN3)ethyl]iminomethyl‐κN}‐5‐methylphenolato‐κO)manganese(I), fac‐[Mn(C16H14N3O4)(CO)3], (II), display facial coordination in a distorted octahedral environment. The crystal structure of (I) is stabilized by O—H...O, N—H...O and C—H...O hydrogen‐bond interactions, while that of (II) is stabilized by N—H...O hydrogen‐bond interactions only. These interactions result in two‐dimensional networks and π–π stacking for both structures.  相似文献   

15.
In catena‐poly­[[[tri­aqua­cadmium(II)]‐μ‐acetyl­enedi­carboxyl­ato‐κ4O,O′:O′′,O′′′] hydrate], {[Cd(C4O4)(H2O)3]·­H2O}n, the CdII atom is coordinated by two bidentate carboxyl­ate groups and three water mol­ecules, thus forming a sevenfold coordination polyhedron with all atoms located on general sites. These polyhedra are connected by the bifunctional acetyl­enedi­carboxyl­ate ligands, forming zigzag chains running parallel to [120]. Hydro­gen bonds, which involve the non‐coordinated water mol­ecule, connect these chains to form a three‐dimensional framework.  相似文献   

16.
The binuclear praseodymium(III) complex with N‐(1‐carboxyethylidene)‐salicylhydrazide (C10H10N2O4, H2L) was prepared in H2O‐C2H5OH mixed solution, and the crystal structure of [Pr2L2(HL)2(H2O)4]·3H2O·C6H6 was determined by X‐ray single crystal diffraction. The crystal complex crystallizes in the triclinic system with space group P‐1, and in the structure each Pr atom is 9‐coordinated by carboxyl O and acyl O and azomethine N atoms of two tridentate ligands to form two stable five‐membered rings sharing one side in keto‐mode and two water molecules. The coordination polyhedron around Pr3+ was described as a monocapped square antiprism geometry. In an individual molecule, four tridentate ligands were coordinated by two negative univalent (HL) and two bivalent forms (L) respectively. Two negative univalent ligands were coordinated via μ2‐bridging mode.  相似文献   

17.
The design and synthesis of new organic lgands is important to the rapid development of coordination polymers (CPs). However, CPs based on asymmetric ligands are still rare, mainly because such ligands are usually expensive and more difficult to synthesize. The new asymmetric ligand 4‐[4‐(1H‐imidazol‐1‐yl)phenyl]pyridine (IPP) has been used to construct the title one‐dimensional coordination polymer, catena‐poly[[[aqua{4‐[4‐(1H‐imidazol‐1‐yl‐κN3)phenyl]pyridine}cadmium(II)]‐μ‐5‐hydroxybenzene‐1,3‐dicarboxylato‐κ3O1,O1′:O3] monohydrate], {[Cd(C8H4O5)(C14H11N3)2(H2O)]·H2O}n, under hydrothermal reaction of IPP with CdII in the presence of 5‐hydroxyisophthalic acid (5‐OH‐H2bdc). The CdII cation is coordinated by two N atoms from two distinct IPP ligands, three carboxylate O atoms from two different 5‐OH‐bdc2− dianionic ligands and one water O atom in a distorted octahedral geometry. The cationic [Cd(IPP)2]2+ nodes are linked by 5‐OH‐bdc2− ligands to generate a one‐dimensional chain. These chains are extended into a two‐dimensional layer structure via O—H…O and O—H…N hydrogen bonds and π–π interactions.  相似文献   

18.
A potentially pentadentate hydrazone ligand, N′‐[1‐(pyrazin‐2‐yl)ethylidene]nicotinohydrazide (HL), was prepared from the condensation reaction of nicotinohydrazide and acetylpyrazine. Reactions of HL with MnCl2, Mn(CH3COO)2 and Cd(CH3COO)2 afforded three metal complexes, namely dichlorido{N′‐[1‐(pyrazin‐2‐yl‐κN1)ethylidene]nicotinohydrazide‐κ2N′,O}manganese(II), [MnCl2(C12H11N5O)], (I), bis{N′‐[1‐(pyrazin‐2‐yl‐κN1)ethylidene]nicotinohydrazidato‐κ2N′,O]manganese(II), [Mn(C12H10N5O)2], (II), and poly[[(acetato‐κ2O,O′){μ3N′‐[1‐(pyrazin‐2‐yl‐κ2N1:N4)ethylidene]nicotinohydrazidato‐κ3N′,O:N1}cadmium(II)] chloroform disolvate], {[Cd(C12H10N5O)(CH3COO)]·2CHCl3}n, (III), respectively. Complex (I) has a mononuclear structure, the MnII centre adopting a distorted square‐pyramidal coordination. Complex (II) also has a mononuclear structure, with the MnII centre occupying a special position (C2 symmetry) and adopting a distorted octahedral coordination environment, which is defined by two O atoms and four N atoms from two N′‐[1‐(pyrazin‐2‐yl)ethylidene]nicotinohydrazidate (L) ligands related via a crystallographic twofold axis. Complex (III) features a unique three‐dimensional network with rectangular channels, and the L ligand also serves as a counter‐anion. The coordination geometry of the CdII centre is pentagonal bipyramidal. This study demonstrates that HL, which can act as either a neutral or a mono‐anionic ligand, is useful in the construction of interesting metal–organic compounds.  相似文献   

19.
The crystal structure of the title complex, trans‐dichloridotetrakis[1‐phenyl‐3‐(1H‐1,2,4‐triazol‐1‐yl‐κN4)propan‐1‐one]copper(II) hexahydrate, [CuCl2(C11H11N3O)4]·6H2O, is isomorphous with that of the corresponding nickel and cobalt compounds. The complex has crystallographic inversion symmetry with the CuII atom on an inversion centre. Each CuII atom is six‐coordinated by one N atom from each of the four 1‐phenyl‐3‐(1H‐1,2,4‐triazol‐1‐yl)propan‐1‐one ligands in the equatorial plane and by two chloride ligands in axial positions. The structure includes a centrosymmetric irregular up–up–down–down (uudd) water tetramer cluster and O—H...Cl hydrogen bonds. Intermolecular C—H...Cl hydrogen bonds exist between adjacent molecules, resulting in a three‐dimensional supramolecular network.  相似文献   

20.
The ionic title complex, bis(μ‐ethylene glycol)‐κ3O,O′:O′;κ3O:O,O′‐bis[(ethylene glycol‐κ2O,O′)(ethylene glycol‐κO)sodium] bis(ethylene glycolato‐κ2O,O′)copper(II), [Na2(C2H6O2)6][Cu(C2H4O2)2], was obtained from a basic solution of CuCl2 in ethylene glycol and consists of discrete ions interconnected by O—H...O hydrogen bonds. This is the first example of a disodium–ethylene glycol complex cation cluster. The cation lies about an inversion center and the CuII atom of the anion lies on another independent inversion center.  相似文献   

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