Gold–germanium complexes

Abstract

The gold–germanium bond in the complex Ph₃PAuGePh₃(I) is cleaved by a variety of halides [HCl, HgCl₂, CCl₄, C₂H₄Br₂, C₂H₄Cl₂, Mel, Ph₃PAuCl, and (Et₃P)₂PtCl₂]. Oxidation by air is catalysed by peroxides. Cleavage by magnesium bromide gives the germyl Grignard reagent, Ph₃GeMgBr, whilst tin(IV) chloride forms gold–tin complexes, (Ph₃P)_nAuSnCl₃. Triethylphosphine and the chelate, Ph₂PCH₂CH₂PPh₂, displace triphenylphosphine from (I), and the former, with limited access of air, yields a triethylphosphine gold(0) complex. Carbon monoxide also gives evidence of a gold(0) complex in its reaction with (I). The trimethylgermyl complex, Ph₃PAuGeMe₃ is obtained in low yield by the reaction between Ph₃PAuCl and (Me₃Ge)₂Hg.