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1.
The reaction of Pb(CH3COO)2·3H2O with N‐benzesulfonyl‐L‐glutamic acid in the presence of 2, 2′‐bipyridine (bipy) or 1,10‐phenanthroline (phen) produced two novel complexes [Pb2(Bs‐glu)2(bipy)2] ( 1 ) and [Pb2(Bs‐glu)2(phen)2] ( 2 ) (Bs‐glu = N‐benzesulfonyl‐L‐glutamic acid dianion). In 1 chains bearing alternative 16‐membered rings and Pb2O3 nodes are constructed from the interactions of PbII ions with the carboxylates of Bs‐glu ligands. To the best of our knowledge, this is the first lead(II) complex of carboxylates with the formation of chains of Pb2O3. In 2 the 16‐membered ring units are connected by centrosymmetric Pb2O2 nodes to form chains. Complexes 1 and 2 construct the 3‐D supramolecular architectures through versatile hydrogen bonds and π‐π stacking interactions. 相似文献
2.
The palladium(II) and platin(II) 1, 1‐dicyanoethylene‐2, 2‐dithiolates [(L–L)M{S2C=C(CN)2}] (M = Pd: L–L = dppm, dppe, dcpe, dpmb; M = Pt: dppe, dcpe, dpmb) were prepared either from[(L–L)MCl2] and K2[S2C=C(CN)2] or from [(PPh3)2M{S2C=C(CN)2}] and the bisphosphane. Moreover, [(dppe)Pt{S2C=C(CN)2}]was obtained from [(1, 5‐C8H12)Pt{S2C=C(CN)2}] and dppeby ligand exchange. The 1, 1‐dicyanoethylene‐2, 2‐diselenolates[(dppe)M{Se2C=C(CN)2}] (M = Pd, Pt) were prepared from[(dppe)MCl2] and K2[Se2C=C(CN)2]. The oxidation potentials of the square‐planar palladium and platinum complexes were determined by cyclic voltammetry. The reaction of [(dcpe)Pd(S2C=O)] with TCNE led to a ligand fragment exchange and gave the 1, 1‐dicyanoethylene‐2, 2‐dithiolate [(dcpe)Pd{S2C=C(CN)2}] in good yield. 相似文献
3.
A zero-valent [M(Ph(2)PCH(2)CH(2)PPh(2))(2)] moiety (M = Mo, W) generated in situ by dissociation of the N(2) ligands in trans-[M(N(2))(2)(Ph(2)PCH(2)CH(2)PPh(2))(2)] can activate pi-accepting organic molecules including isocyanides and nitriles, which undergo the electrophilic attack caused by a strong pi-donation from a zero-valent metal center. Cleavage of a variety of C-X bonds (X = H, C, N, O, P, halogen) also occurs at their electron-rich sites through oxidative addition to form reactive intermediates, which subsequently degradate to yield smaller molecules either bound to or dissociated from the metal center. The mechanism is substantiated unambiguously by isolation of numerous intermediate stages. 相似文献
4.
By reaction of organo‐functionalized germanium or tin sesquisulfides [(R1T)4S6] (T = Ge, Sn; R1 = CMe2CH2COMe) with thiosemicarbazide or its methyl or phenyl derivative, a series of four compounds were obtained and structurally characterized that are based on an inorganic (TS2)2 unit with an extended organic chelate ligand CMe2CH2CMeNNCSNHR′ (R′ = H, Me, Ph). The products combine a small, reactive metal chalcogenide moiety with a ligand system that allows for a variety of directed extensions at the terminal NHR′ group. Thus, this work represents the starting point to a multifaceted consecutive chemistry involving both the extension of the binary inorganic unit and further derivatization and/or coordination of the organic ligands. 相似文献
5.
Two supramolecular architectures, [Mn(3‐bpd)2(NCS)2(H2O)2]·2H2O ( 1 ) and {[Mn(bpe)(NCS)2(H2O)2]·(3‐bpd)·(bpe)·H2O}n ( 2 ) [bpe = 1,2‐bis(4‐pyridyl)ethylene and 3‐bpd = 1,4‐bis(3‐pyridyl)‐2,3‐diaza‐1,3‐butadiene] have been synthesized and characterized by spectroscopic, elemental and single crystal X‐ray diffraction analyses. Compound 1 crystallizes in the monoclinic system, space group P21/c, with chemical formula C26H28Mn N10O4S2, a = 9.1360(6), b = 9.7490(6), c = 17.776(1) Å, β = 93.212(1)°, and Z = 2 while compound 2 crystallizes in the orthorhombic system, space group P212121, with chemical formula C38H36Mn1N10O3S2, a = 14.1902(6), b = 15.4569(7), c = 18.2838(8) Å, α = β = γ = 90°, and Z = 4. Structural determination reveals that the coordination geometry at Mn(II) in compound 1 or 2 is a distorted octahedral which consists of two nitrogen donors of two NCS?ligands, two oxygen donors of two water molecules, and two nitrogen donors of two 3‐bpd ligands for 1 and two dpe ligands for 2 , respectively. The two 3‐bpd ligands in 1 adopt a monodentate binding mode and the dpe in 2 adopts a bismonodentate bridging mode to connect the Mn(II) ions forming a 1D chain‐like coordination polymer. Both the π‐π stacking interactions between the coordinated and the free pyridyl‐based ligands and intermolecular hydrogen bonds among the coordinated and the crystallized water molecules and the free pyridyl‐based ligands play an important role in construction of these 3D supramolecular architectures. 相似文献
6.
以3-叠氮-1,2,4-三唑为配体,PA–(苦味酸根)或HTNR–(2,4,6-三硝基间苯二酚脱去一个羟基的质子后形成的离子)为外阴离子,制备得到了两种新的配合物:[Zn(AZT)4(H2O)2](PA)2∙4H2O和[Zn(AZT)2(H2O)4](HTNR)2∙4H2O。[Zn(AZT)4(H2O)2](PA)2∙ 4H2O的X射线晶体数据表明,中心Zn2+离子与来自4个AZT分子的N原子和2个H2O分子的O原子配位;而对于[Zn(AZT)2(H2O)4](HTNR)2∙4H2O来说,6个配位原子来自2个AZT分子的N原子和4个H2O分子的O原子。在两种配合物中,AZT配体分子的配位点都是三唑环上的4位N原子。H2O分子对于分子间氢键的形成起到了重要的作用,在分子间氢键的作用下形成了配合物的晶体结构。在[Zn(AZT)4(H2O)2](PA)2∙4H2O的晶体结构中,还存在错位面对面π-π堆积作用,它对于晶体结构的形成和稳定性也起到了重要作用。TG-DTG和DSC分析结果显示,[Zn(AZT)2(H2O)4](HTNR)2∙4H2O的热分解过程不如[Zn(AZT)4(H2O)2](PA)2∙4H2O剧烈,原因在于前者分子中含有较多配位水分子和较少AZT配体分子。感度测试结果表明,[Zn(AZT)4(H2O)2](PA)2∙4H2O有一定的火焰感度,而[Zn(AZT)2(H2O)4](HTNR)2∙4H2O却对热不敏感;两种化合物在撞击和摩擦作用下都表现钝感。 相似文献
7.
(NH3CH2CH2NH2)3[Mo(Ⅴ)O2(O2C6H4)2] (1), (NH3CH2CH2NH2)2.5[Mo(Ⅴ)o.sW(Ⅵ)o.502(O2C6H4)2] (2) and(NH3CH2CH2NH2)2[VC(Ⅵ)O2(O2C6H4)2] (3) were synthesized, structurally characterized by X-ray diffraction analysis, and studied on their interactions with ATP, their DNA cleavage activities and antitumor properties. The redox state of molybdenum was not changed on going from crystal to aqueous solutions in complexes 1 and 2, while tungsten underwent reduction from W(VI) to W(V) in complexes 2 and 3. ATP promoted the oxidation of both molybdenum and tungsten from M(Ⅴ) to M(Ⅵ) and the hydrolysis of catecholate ligands in solution consisting of ATP and the complexes. Complex 1 possesses fairly good activity to DNA cleavage and against tumor S180 in mice, and is more effective than the control drug cyclophosphamide under the identical conditions. However, complexes 2 and 3 exhibited marginal effectiveness. The effectiveness of anti-tumor of the complexes was related positively to their DNA cleavage activities and their hydrolysis of catecholate ligands. 相似文献
8.
Bis(tetraphenylphosphonium) hexachloridodiberyllate, (Ph4P)2[Be2Cl6], reacts with excess trimethylsilyl‐iso‐thiocyanate to give a mixture of colourless single crystals of (Ph4P)2[Be(NCS)4] ( 1 ) and (Ph4P)4[{Be2(NCS)4(μ‐NCS)2}{Be2(NCS)6(μ‐H2N2C2S2)}] ( 2 ), which can be separated by selection. Both complexes were characterized by X‐ray diffraction. Compound 1 can be prepared without by‐products by treatment of (Ph4P)2[BeCl4] with excess Me3SiNCS in dichloromethane solution. 1 : Space group I41/a, Z = 4, lattice dimensions at 100(2) K: a = b = 1091.2(1), c = 3937.1(3) pm, R1 = 0.0474. The [Be(NCS)4]2– ion of 1 forms tetragonally distorted tetrahedral anions with Be–N distances of 168.4(2) pm and weak intermolecular S ··· S contacts along [100] and [010]. 2 ·4CH2Cl2: Space group P , Z = 1, lattice dimensions at 100(2) K: a = 919.5(1), b = 1248.3(1), c = 2707.0(2) pm, α = 101.61(1) °, β = 95.08(1) °, γ = 94.52(1) °, R1 = 0.103. Compound 2 contains two different anionic complexes in the ratio 1:1. In {Be2(NCS)4(μ‐NCS)2}2–, the beryllium atoms are connected by (NCS)– bridging groups forming centrosymmetric eight‐membered Be2(NCS)2 rings with distances Be–N of 168(1) pm and Be–S of 235.2(9) pm. The second anion {Be2(NCS)6(μ‐H2N2C2S2)}2– consists of two {Be(NCS)3}– units, which are linked by the nitrogen atoms of the unique dimeric cyclo‐addition product of HNCS with Be–N distances of 179(1) pm. 相似文献
9.
Two trans‐bis(saccharinato) (sac) complexes of cadmium(II ) with 2‐aminomethylpyridine (ampy) and 2‐aminoethylpyridine (aepy) were synthesized and characterized by means of elemental analysis, FT‐IR spectroscopy and thermal analysis. In addition, their solid‐state structures were determined by single crystal X‐ray diffraction studies. The [Cd(sac)2(ampy)2] ( 1 ) and [Cd(sac)2(aepy)] ( 2 ) complexes consist of neutral monomeric units and crystallize in the orthorhombic (Pbca) and monoclinic (P21/c) crystal systems, respectively. The cadmium(II ) ions in 1 and 2 sit on inversion centres andexhibit distorted octahedral coordination by two sac anions and two aminopyridine ligands. The sac ligands in both complexes are N‐coordinated and located in trans positions, while the ampy and aepy ligands act as a bidentate ligand forming two symmetrically chelate rings around cadmium(II ). IR spectra and thermal decompositions of the complexes are also discussed. 相似文献
10.
Calcium biuretooxophosphate Ca[PO2(NH)3(CO)2]2 was synthesized by ion exchange reaction in aqueous solution. The crystal structure of the salt was elucidated by single‐crystal X‐ray diffraction. Anionic 1‐phospha‐2, 4, 6‐s‐triazine rings exhibiting a half‐chair conformation act as monodentate ligands for the calcium ions. A 3D network is formed by the resulting CaO6 octahedrons together with the anionic rings interconnected by hydrogen bonds. Beside the crystal structure, FTIR and photoluminescence spectra of calcium biuretooxophosphate are discussed. The thermal behavior of the salt is examined by means of temperature‐dependent powder X‐ray diffraction measurements and combined TG and DTA analyses. 相似文献
11.
Jochen Glaser Simone Dill Michael Marzini Hermann A. Mayer H.‐Jürgen Meyer 《无机化学与普通化学杂志》2001,627(5):1090-1094
(Meta)stable CaC2 One out of four modifications of CaC2 is the so‐called metastable Calcium Carbide, CaC2‐III, which was synthesized as pure material. It forms by heating monoclinic CaC2‐II (C2/c) above 150 °C and remains stable after cooling down to room temperature. The structure was refined from X‐ray powder patterns (C2/m, Z = 4, a = 722.6(1) pm, b = 385.26(7) pm, c = 737.6(1) pm, β = 107.345(2)°). After grinding CaC2‐III transforms back into CaC2‐II. Heating CaC2‐III induces a reversible phase transition into the cubic modification (CaC2‐IV) at 460 °C. Differences between the three different structures of CaC2 I–III, being stable at ambient conditions are also shown by 13C‐MAS‐NMR measurements, especially the presence of two distinct types of carbon atoms in the structure of the title compound. 相似文献
12.
Judith Caballero‐Jimnez Yasmi Reyes Ortega Sylvain Berns Roberto Escudero 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(8):754-757
The title complex, catena‐poly[di‐μ3‐acetato‐κ6O:O:O′‐tetra‐μ2‐acetato‐κ4O:O;κ4O:O′‐diaquabis(pyridine‐κN)trimanganese(II)], [Mn3(CH3COO)6(C6H5N)2(H2O)2]n, is a true one‐dimensional coordination polymer, in which the MnII centres form a zigzag chain along [010]. The asymmetric unit contains two metal centres, one of which (Mn1) lies on an inversion centre, while the other (Mn2) is placed close to an inversion centre on a general position. Since all the acetates behave as bridging ligands, although with different μ2‐ and μ3‐coordination modes, a one‐dimensional polymeric structure is formed, based on trinuclear repeat units (Mn1...Mn2...Mn2′), in which the Mn2 and Mn2′ sites are related by an inversion centre. Within this monomeric block, the metal–metal separations are Mn1...Mn2 = 3.36180 (18) Å and Mn2...Mn2′ = 4.4804 (3) Å. Cation Mn1, located on an inversion centre, displays an [MnO6] coordination sphere, while Mn2, on a general position, has a slightly stronger [MnO5N] ligand field, as the sixth coordination site is occupied by a pyridine molecule. Both centres approximate an octahedral ligand field. The chains are parallel in the crystal structure and interact via hydrogen bonds involving coordinated water molecules. However, the shortest metal–metal separation between two chains [5.3752 (3) Å] is large compared with the intrachain interactions. These structural features are compatible with a single‐chain magnet behaviour, as confirmed by preliminary magnetic studies. 相似文献
13.
Phosphoraneiminato Acetate Cluster of Copper and Zinc. Crystal Structures of [Cu4(NPEt3)2(O2CCH3)6] and [Zn4(NPEt3)2(O2CCH3)6] The anhydrous acetates of copper(II) and zinc react with the silylated phosphaneimine Me3SiNPEt3 in dichloromethane at 20 °C forming the mixed phosphoraneiminato acetate clusters [Cu4(NPEt3)2(O2CCH3)6] ( 1 ), which forms emerald crystals, and colourless [Zn4(NPEt3)2 · (O2CCH3)6] ( 2 ). In spite of analogous composition the structures of 1 and 2 are completely different. In the asymmetric unit of 1 three copper atoms of an almost isosceles triangle are linked via two nitrogen atoms of the NPEt3– groups to form a trigonal bipyramidal aggregate. One of these three copper atoms is chelated by an acetate group, another one is connected with the fourth copper atom via three μ2‐O2C–CH3 groups. The asymmetric units are associated via a μ2‐O2C–CH3 group and a μ3‐OC(O)CH3 group at a time so that infinite chains result. In 2 two zinc atoms are linked via the nitrogen atoms of the two NPEt3– groups to form an almost centrosymmetric four‐membered ring. Both nitrogen atoms of the four‐membered ring are connected with another zinc atom each. These zinc atoms again are linked with the zinc atoms of the Zn2N2 four‐membered ring via two μ2‐O2C–CH3 groups each and additionally coordinated with a terminal acetate ligand each. 相似文献
14.
A series of 3,3′‐(benzylene)bis(4‐hydroxy‐2H‐chromen‐2‐one) derivatives have been synthesized from condensation reactions of 4‐hydroxycoumarin with benzaldehydes under thermal solvent‐free conditions. This environmentally friendly synthesis is uncatalyzed and affords the desired products in excellent yields. 相似文献
15.
Meng Y Yan BZ Wang HM Hu GF Liu FY Song YG Liu Y 《Magnetic resonance in chemistry : MRC》2004,42(6):564-566
1H and 13C NMR spectra of 8-C-beta-D-[2-O-(E)-p-coumaroyl] glucopyranosyl-2-(2-hydroxy)propyl-7-methoxy-5-methylchromone were completely assigned by 2D NMR observations. Especially the 1H assignments of the glucosyl and hydroxyl protons were achieved by utilizing HMQC, HMBC, 1H-1H COSY and DEPT techniques together with a heavy water exchange 1H NMR experiment. 相似文献
16.
17.
Dyer MS Darling GR Claridge JB Rosseinsky MJ 《Angewandte Chemie (International ed. in English)》2012,51(14):3418-3422
Repeating boundaries: The buried interfaces in artificial heterostructures produced by sequential deposition of nanosized units are critical to their properties. With density functional theory it was shown that in Y(2) O(3) :ZrO(2) (YSZ) and SrTiO(3) (STO) heterostructures reconstruction of the interfaces between the component units is required to access the most favorable structure. 相似文献
18.
J. M. Morsy 《中国化学会会志》2008,55(6):1243-1250
3‐Aroyl‐2‐arylpropionic acids 2a‐e were utilized to synthesize 3(2H)‐pyridazinones 3a‐e and 2(3H)‐furanones 6 through reaction with hydrazine hydrate and freshly distilled acetic anhydride, respectively, in the hope of obtaining new 3(2H)‐pyridazinones with no ulcerogenic side effect or with negligible general side effects as those currently used NSAIDS as well as biologically active 2(3H)‐furanones. 相似文献
19.
Al-Rafia SM Malcolm AC McDonald R Ferguson MJ Rivard E 《Angewandte Chemie (International ed. in English)》2011,50(36):8354-8357
Putting on some weight: A series of stable adducts featuring the hitherto unknown mixed heavy ethylene analogues H(2) SiGeH(2) and H(2) SiSnH(2) were prepared using a versatile donor-acceptor method. 相似文献
20.
Poulsen RD Jørgensen MR Overgaard J Larsen FK Morgenroth W Graber T Chen YS Iversen BB 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(35):9775-9790
Three high-quality single-crystal X-ray diffraction data sets have been measured under very different conditions on a structurally simple, but magnetically complex, coordination polymer, [Mn(HCOO)(2)(H(2)O)(2)](infinity) (1). The first data set is a conventional 100(2) K Mo(Kalpha) data set, the second is a very high resolution 100(2) K data set measured on a second-generation synchrotron source, while the third data set was measured with a tiny crystal on a high brilliance third-generation synchrotron source at 16(2) K. Furthermore, the magnetic susceptibility (chi) and the heat capacity (C(p)) have been measured from 2 to 300 K on pressed powder. The charge density of 1 was determined from multipole modeling of the experimental structure factors, and overall there is good agreement between the densities obtained separately from the three data sets. When considering the fine density features, the two 100 K data sets agree well with each other, but show small differences to the 16 K data set. Comparison with ab initio theory suggests that the 16 K APS data set provides the most accurate density. Topological analysis of the metal-ligand bonding, experimental 3d orbital populations on the Mn atoms, and Bader atomic charges indicate quite ionic, high-spin metal atoms. This picture is supported by the effective moment estimated from the magnetization measurements (5.840(2) mu(B)), but it is at variance with earlier spin density measurements from polarized neutron diffraction. The magnetic ordering originates from superexchange involving covalent interactions with the ligands, and non-ionic effects are observed in the static deformation density maps as well as in plots of the valence shell charge concentrations. Overall, the present study provides a benchmark charge density that can be used in comparison with future metal formate dihydrate charge densities. 相似文献