Close Correlation between Metal Oxidation States and Molecular Structures in a Cobalt–Gold Multinuclear Coordination System with Mixed D‐Penicillaminate and Tripodal Triphosphine

Abstract

AbstractA unique cobalt–gold coordination system, in which the oxidation states of the cobalt centers are closely correlated with the multinuclear molecular structures, is reported. This system contains a CoII3AuI6 nonanuclear structure in [Co3{Au3(tdme)(D‐pen‐N,O,S)3}2] ([2]) and a CoIIIAuI3 tetranuclear structure in [Co{Au3(tdme)(D‐pen‐N,S)3}] ([3]) [tdme = 1,1,1‐tris(diphenylphosphinomethyl)ethane, D‐pen = D‐penicillamininate], which are stereoselectively prepared from the reaction of a tripod‐type trigold(I) metalloligand [Au3(tdme)(D‐pen)3]3– ([1]3–) with Co2+ and Co3+, respectively. The anomalous stability of the +II oxidation state of each octahedral cobalt center in [2], despite the coordination of two aliphatic amine and two aliphatic thiolato groups that commonly provide a strong ligand field, is notable.