Synthesis, crystal structure of diferrous complex and its reactivity with dioxygen
The dinuclear complex of [ Fe2L{ O2P(OPh)2} ] (ClO4)2·Et2O(1) (where L represents the dinucleating ligand N-Et-HPTB, anion of N, N, N′, N′-tetrakis (N-ethyl-2-benzimidazolyemethyl)- 2-hydroxy-1, 3-diamino-propane) has been synthesized and crystallizes in the triclinic space group P with cell constants a = 1.526(3) nm, b = 1.259 8(3) nm, c = 1.563 0(3) nm , α= 94.41(3)°, β= 115.31(3)°, γ = 99.90(3)°, V = 3.267(1) nm3, z = 2, R = 0.084 7 and Rw = 0.177 8. The Fe(Ⅱ) sites are bridged by an alkoxide of the dinucleating ligand and a phosphate, affording a diiron core with an Fe-μ-O-Fe angle of 131.20(3)° and an Fe-Fe distance of 0.364 9 nm. Both Fe(Ⅱ) centers have trigonal bipyramidal geometry. Dioxygen adduct (1/O2) forms upon exposure of the diferrous complex to O2 at low temperature (-60℃). The 1/O2 adduct is stable at -60℃ but decomposes upon warming. The adduct exhibits visible absorption maximum near 606 nm and resonance Raman features at 478 cm-1 (γFe-O) and 897 cm-1 (γO-O), and the latter is the characteristic of a μ-1,2-peroxo species, indicating that dioxygen adducts can serve as models for the putative oxygenated intermediate of some non-heme diiron-oxo proteins.
作 者： YAN Shiping CHENG Peng WANG Qinglun LIAO Daizheng JIANG Zonghui WANG Genglin 作者单位： Department of Chemistry, Nankai University, Tianjin 300071, China 刊 名： 中国科学B辑（英文版） EI SCI 英文刊名： SCIENCE IN CHINA (SERIES B) 年，卷(期)： 2000 43(4) 分类号： O6 关键词： diiron complex model compound activation of dioxygen