The Mo(Ⅴ) and W(Ⅵ) complexes of (NH3CH2- CH2NH2)3[Mo(Ⅴ)O2(OC6H4O)2] (1), (NH3CH2CH2NH2)2.5 [Mo(Ⅴ) 0.5W(Ⅵ)0.5O2(OC6H4O)2] (2) and (NH3CH2CH2NH2)2- [W(Ⅵ)O2(OC6H4O)2] (3) were synthesized by choosing cate-chol ligand which shows a good reductive property and tak-ing advantage of EMo > EW. Their EPR and UV-vis spectra were compared with the oxidized UV-vis spectra of xanthine dehydrogenase from chicken liver and xanthine oxidase from milk and the EPR spectrum of flavoenzyme from milk.
LU XiaomingLIU ShunchengMAO XiYE ZhaohuiLU Jingfen
[H2N(CH2)3NH312[MoO2(C10H6O2)2] (1) was synthesized by the 2,3-dihydroxynaphthalene in the mixed solvent of CH3OH, CH3CN reaction of (n-Bu4N)4[Mo8O26] with and 1,3-propanediarnine. (C5HllN2)2- [HeN(CH2)3NH2][MoO2(CloH6O2)2] (2) was obtained by the reaction of Na2MoO4.2H20 with 2,3-dihydroxynaphthalene in the same solvent above. Both of the complexes possess complex anion [Mo(VI)O2(OC10H6O)2]^2- which shows pseudo-octahedrally coordinated fashion, while the counterions are two protonated 1,3-propanediamine in complex 1 and (CsH11N2)^+ in complex 2. (C5H11N2)+ is the byproduct of reaction 2, which results from combination of acetonitrile with 1,3-propanediamine. Packing diagrams of the two complexes are also different. There is anti-parallel-aligned-double-meso-bilayer unit in complex 1. However there are four chiral anions arranged in anticlockwise orientation in complex 2.
Cis-dioxo-catecholatotungsten(V) complex (NH2CH2CH2NH3)4[WⅤO2(OC6H4O)2]2(NH3CH2CH2NH3)·H2O (1) was synthesized at room temperature by the reaction of tetrabutyl ammonium decatungstate with catechol in the mixed solvent of CH3OH, CH3CN and NH2CH2CH2NH2. The crystal structure of complex was determined by X-ray diffraction structural analysis. The results show that complex belongs to monoclinic system with space group P21 / c, a=0.712 8(3) nm, b=3.082 3(11) nm, c=0.982 8(4) nm, β=102.639(6)°, V=2.106 8(14) nm3, Z=2, R1=0.062 8, wR2=0.183 7. Compared the complex with its analogous complexes (NH2CH2CH2NH3)3[MoⅤO2(OC6H4O)2], it is found that the coordination structure of W have no changes in the processing of electron transfer of tungsten-containing enzymes from the result of the similarity of the EPR spectra of the complexes and flavoenzyme from milk. CCDC: 272937.
Cis-dioxo-tungsten(Ⅵ ) complex, (NH2CH2CH2NH2)[(NH2CH2CH2NH3)2WⅥO2(NHC6H4NH)2]2·H2O is synthesized at room temperature by the reaction of sodium tungstate with o-phenylenediamine. The crystal structure of complex was determined by X-ray diffraction structural analysis. The results show that complex belongs to monoclinic system with space group P21 / c, a=0.712 8(2) nm, b=3.081 1(10) nm, c=0.981 9(3) nm, β=102.615(4)°, V=2.104 4(11) nm3, Z=2, μ=55.26 cm-1, F(000)=1 176. Compared the complex with its analogous biomimetic complexes of the cofactor of molybdoenzymes and tungstoenzymses, it is found that the variance of the coordination atoms and the metal ions center have no influence on the coordination feature, and exhibits distored octahedral coordination with cis-dioxo o-phenylenediamine. CCDC: 252834.