Synthesis, Molecular Structure, and Catalytic Potential of the Tetrairon Complex [Fe4(N3O2-L)4(μ-O)2]4+ (L = 1-Carboxymethyl-4,7-dimethyl-1,4,7-triazacyclononane)

摘要: The reaction of iron sulfate with 1-carboxymethyl-4,7-dimethyl-1,4,7-triazacyclononane (L) and hydrogen peroxide in aqueous ethanol gives a brown dinuclear complex considered to be [Fe2(N3O-L)2(μ-O)(μ-OOCCH3)] + (1), which converts upon standing acetonitrile solution into the green tetranuclear [Fe4(N3O2-L)4(μ-O)2]4+ (2). A single-crystal X-ray structure analysis [2][PF6]4·5MeCN reveals 2 contain four iron(III) centers, each is coordinated three nitrogen atoms triazacyclononane ligand bridged by one oxo two carboxylato bridges, structural feature known from active center methane monooxygenase. Accordingly, was found catalyze oxidative functionalization give methanol, methyl hydroperoxide, formic acid; total turnover numbers attain 24 catalytic cycles within 4 h. To gain more insight process, potential also studied for oxidatio...