Halogenation of (phosphine chalcogenide)gold(i) halides; some unexpected products

Abstract

The monoselenide of 1,8-bis(diphenylphosphino)naphthalene reacts with (tht)AuCl to give the gold(III) system [(dppnAuSe)₂]²⁺ 2Cl⁻ (1); bromination of the bromogold(I) complex of the 1,2-bis(diphenylphosphino)methane monosulfide ligand furnishes the tribromide salt (2a) of a gold(III) cation [LAuBr₂]⁺; bromination of the bromogold(I) complex of the 1,2-bis(diphenylphosphino)benzene monosulfide ligand leads to a mixed bromide/tetrabromoaurate salt (3) of a heterocyclic dication involving a [-PPh₂-S-PPh₂-]²⁺ moiety; analogous reactions of triphenylphosphine sulfide and selenide complexes lead to tetrabromoaurate salts (4a and 4b) of the (bromochalcogeno)phosphonium cations Ph₃PEBr⁺.