A pyrazole-substituted diiron dithiolate complex [Fe2(μ-pdt)(CO)5(3,5-Me2Pz)](1,3,5-Me 2Pz=3,5-dimethylpyrazole) was prepared as a biomimetic model for the active site of [FeFe]-hydrogenase by CO-substitution of all-carbonyl complex [Fe2(μ-pdt)(CO)6] with 3,5-Me2Pz. The molecular structure was confirmed by MS, IR, 1H NMR, elemental analysis and single-crystal X-ray analysis. Complex 1 crystallizes in the triclinic system, space group P1 with a=9.108(7), b=9.743(8), c=11.192(9), α=109.235(5), β=101.914(9), γ=96.605(6)o. In CH3CN solution, reversible transformation between 1 and the acetonitrile-substituted species [Fe2(μ-pdt)-(CO)5(NCCH3)] was detected by both IR and cyclic voltammetry (CV). The electrochemical proton reduction catalyzed by 1 in the presence of acetic acid was also studied in CH2Cl2.
Two new coordination polymers, [Cd(N3)2(Baep)1/2]n(1) and [Cd2(N3)4(CH3OH)(Bapp)1/2]n(2) (Baep=1,4-bis(2-aminoethyl)piperazine, Bapp=1,4-bis(3-aminopropyl)piperazine) were synthesized. The crystal of 1 is of monoclinic system, space group P21/c with a=9.341(7), b=11.677(9), c=8.195(6), β=93.925(13)°, V=891.8(11)3 , Z=4, μ(MoKα)=2.42 mm-1 , Mr=280.58, Dc=2.090 g/cm3 , the final R=0.0297 and wR=0.0720. The crystal of 2 is of triclinic system, space group PI with a=9.121(5), b=9.666(5), c=10.250(6), α=72.91(2), β=77.10(2), γ=73.95(2)°, V=820.0(8)3 , Z=2, μ(MoKα)=2.62 mm-1 , Mr=522.10, Dc=2.114 g/cm3, the final R=0.0251 and wR=0.0632. Single-crystal X-ray diffraction studies reveal that 1 is a 3D structure based on a dinuclear unit {Cd2(N3)4(Baep)}, in which the Baep ligands formed in situ display two different bridging modes. Compound 2 also has a 3D structure based on a tetranuclear cluster {Cd4(N3)8(CH3OH)2(Bapp)}, in which the azido anions exhibit four different bridging modes (μ-1,1, μ-1,3, μ-1,1,1 and μ-1,1,3). The thermal stability and fluorescent property of 1 and 2 have also been investigated.
Solvothermal reaction of [WS4]2-with CuCN and trithiocyanuric acid(L1) in orga-nic solvents gave rise to a new W/Cu/S polymer with a 2D anionic network,namely [Et4N]2[WS4Cu3(C3N3S3H1.5)2](1).The anionic layer of 1 is constructed by the T-shaped {WS4Cu3} subunits as nodes and L1 as linkers and features a(4,4) topology.Both 1 and its isomorphous compound [Et4N]2[MoS4Cu3(C3N3S3H1.5)2](2) have been fully characterized by X-ray crystal analysis,IR and microanalyses.Compounds 1 and 2 show optical transitions with band gaps of 2.17 and 1.84 eV,respectively.