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101.
The construction of two unique, high-nuclearity Cu(II) supramolecular aggregates with tetrahedral or octahedral cage units, [(mu(3)-Cl)[Li subset Cu(4)(mu-L(1))(3)](3)](ClO(4))(8)(H(2)O)(4.5) (1) and [[Na(2) subset Cu(12)(mu-L(2))(8)(mu-Cl)(4)](ClO(4))(8)(H(2)O)(10)(H(3)O(+))(2)](infinity) (2) by alkali-metal-templated (Li(+) or Na(+)) self-assembly, was achieved by the use of two newly designed carboxylic-functionalized diazamesocyclic ligands, N,N'-bis(3-propionyloxy)-1,4-diazacycloheptane (H(2)L(1)) or 1,5-diazacyclooctane-N,N'-diacetate acid (H(2)L(2)). Complex 1 crystallizes in the trigonal R3c space group (a = b = 20.866(3), c = 126.26(4) A and Z = 12), and 2 in the triclinic P1 space group (a = 13.632(4), b = 14.754(4), c = 19.517(6) A, alpha = 99.836(6), beta = 95.793(5), gamma = 116.124(5) degrees and Z = 1). By subtle variation of the ligand structures and the alkali-metal templates, different polymeric motifs were obtained: a dodecanuclear architecture 1 consisting of three Cu(4) tetrahedral cage units with a Li(+) template, and a supramolecular chain 2 consisting of two crystallographically nonequivalent octahedral Cu(6) polyhedra with a Na(+) template. The effects of ligand functionality and alkali metal template ions on the self-assembly processes of both coordination supramolecular aggregates, and their magnetic behaviors are discussed in detail.  相似文献   
102.
A density functional theory investigation on a series of sandwich-type transition metal complexes [(CBO)n]2M (n=4–6; M=transition metals) with carbon boronyls (CBO)n as effective aromatic ligands has been presented in this work at B3LYP level. The ground-states of these complexes possess staggered Dnd symmetries, while the corresponding eclipsed Dnh structures exist as transition states with slightly higher energies (within 5.8 kJ/mol). Carbon boronyl complexes [(CBO)n]2M are confirmed to be much more stable than their boron carbonyl isomers [(BCO)n]2M, which, on the other hand, take eclipsed ground-states with Dnh symmetries. The carbon boronyl complexes [(BCO)n]2M proposed in this work parallelize the well-known sandwich-type hydrocarbon complexes [CnHn]2M in coordination chemistry with boronyl groups –BO isolobal to –H atoms in corresponding ligands.  相似文献   
103.
新型有序结构分子聚集体的构筑   总被引:4,自引:0,他引:4       下载免费PDF全文
本文概述了近年来我们在新型有序结构分子聚集体构筑方面取得的一些主要成绩,并展望了今后进一步的研究和发展方向。  相似文献   
104.
Zheng JM  Batten SR  Du M 《Inorganic chemistry》2005,44(10):3371-3373
A unique cyano-bridged copper(II)-copper(I) mixed-valence polymer, {[Cu(3)(CN)(4)(H(2)O)(3)](H(2)O)(2)}(n) (1), has been prepared and structurally determined by X-ray diffraction. The cyanide anions with (mu(2),eta(2)) and (mu(3),eta(2)) bridging modes connect the copper centers into a complicated zeolite-like 3-D network. Of further interest, coordinated and lattice water molecules in this structure form 1-D hydrogen-bonded water tapes consisting of linked cyclic pentamer clusters.  相似文献   
105.
106.
The reaction of Mn(2)(CO)(7)(mu-S(2)) with [CpNi(CO)](2) yielded the paramagnetic new compound Cp(2)Ni(2)Mn(CO)(3)(mu(3)-S)(2) (1) and a new hexanuclear metal product Cp(2)Ni(2)Mn(4)(CO)(14)(mu(6)-S(2))(mu(3)-S)(2) (2). Structurally, compound 1 contains two triply bridging sulfido ligands on opposite sides of an open Ni(2)Mn triangular cluster. EPR and temperature-dependent magnetic susceptibility measurements of 1 show that it contains one unpaired electron. The electronic structure of 1 was determined by Fenske-Hall molecular orbital calculations which show that the unpaired electron occupies a low lying antibonding orbital delocalized unequally across the three metal atoms. The selenium homologue Cp(2)Ni(2)Mn(CO)(3)(mu(3)-Se)(2) (3) was obtained from the reaction of a mixture of Mn(2)(CO)(10) and [CpNi(CO)](2) with elemental selenium and Me(3)NO.2H(2)O. It also has one unpaired electron. Compound 1 reacted with elemental sulfur to yield the dinickeldimanganese compound, Cp(2)Ni(2)Mn(2)(CO)(6)(mu(4)-S(2))(mu(4)-S(5)), 4, which can also be made from the reaction of Mn(2)(CO)(7)(mu-S(2)) with [CpNi(CO)](2) and sulfur. Compound 4 was converted back to 1 by sulfur abstraction using PPh(3). The reaction of Mn(2)(CO)(10) with [CpNi(CO)](2) in the presence of thiirane yielded the ethanedithiolato compound CpNiMn(CO)(3)(mu-SCH(2)CH(2)S) (5), which was also obtained from the reaction of Mn(4)(CO)(15)(mu(3)-S(2))(mu(4)-S(2)) with [CpNi(CO)](2) in the presence of thiirane. Compound 5 reacted with additional quantities of thiirane to yield the new compound CpNiMn(CO)(3)[mu-S(CH(2)CH(2)S)(2)], 6, which contains a 3-thiapentanedithiolato ligand that bridges the two metal atoms. Compound 6 was also obtained from the reaction of Mn(2)(CO)(10) with [CpNi(CO)](2) and thiirane. The molecular structures of the new compounds 1-6 were established by single-crystal X-ray diffraction analyses.  相似文献   
107.
Four new heterotrinuclear complexes have been synthesized and characterized, namely {[Ni(L)2]2[Cu(opba)]}(ClO4)2, where opba denotes o-phenylenebis(oxamato) and L stands for 1,10-phenanthroline(phen) (1), 5-nitro-l,10-phenanthroline(NO2-phen) (2), 2,2′-bipyridyl(bpy) (S) and 4,4′-dimethyl-2,2′-bipyridyl(Me2bpy) (4). The temperature dependence of the magnetic susceptibility of {[Ni(phen)2]2[Cu(opba)]}(ClO4)23H2O has been studied in the 4–300 K range, giving the exchange integral J—109 cm?1. The HMT vs. T plot exhibits a minimum at about 100 K, characteristic of this kind of coupled polymetallic complex with an irregular spin-state structure.  相似文献   
108.
A rigid C2‐symmetric chiral bipyridine ligand Z‐bpy with a triptycene‐like backbone was designed and synthesized from simple chemicals in a scalable route. Using this new ligand, copper(I) catalyzed cyclopropanation of styrenes with commercial ethyl diazoacetate produced various corresponding cyclopropanes in high yields, diastereoselectivity and enantioselectivity up to 97% ee.  相似文献   
109.
110.
Photoelectrochemical(PEC) water splitting is a promising approach for renewable hydrogen production.However,the practical PEC solar-to-fuel conversion efficiency is still low owing to poor light absorption and rapid recombination of charge carriers in photoelectrode.In this work,we report a ternary photoanode with simultaneously enhancement of light absorption and water oxidation efficiency by introducing copper phthalocyanine(CuPc) and nickel iron-laye red double hydroxide(NiFe-LDH) on TiO_2(denoted as TiO_2/CuPc/NiFe-LDH).An experimental study reveals that CuPc loading on TiO_2 bring strong visible light absorption;NiFe-LDH as an oxygen evolution reaction catalyst efficiently accelerates the surface water oxidation reaction.This synergistic effect of CuPc and NiFe-LDH gives enhanced photocurrent density(2.10 mA/cm2 at 0.6 V vs.SCE) and excellent stability in the ternary TiO_2/CuPc/NiFeLDH photoanode.  相似文献   
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