The Formation of Rhenium(V) Complexes with Dihydroxyphosphoranes and Diarylphosphinic Acid Derivatives Generated from Tris(1,2,3-triazolyl)phosphine Oxides.

Tris(1-phenyl-1 H-1,2,3-triazol-4-yl)phosphine oxide (OP(1,2,3Tz1-Ph)3) and tris(1-benzyl-1 H-1,2,3-triazol-4-yl)phosphine oxide (OP(1,2,3Tz1-benz)3) react with (NBu4)[ReOCl4] under partial hydrolysis and formation of rhenium(V) complexes with unprecedented dihydroxyphosphoranato or diarylphosphinato ligands. Anionic, binuclear complexes of the compositions [Cl3(O)Re{O2P(1,2,3Tz1-Ph)3}Re(O)Cl2]- and [Cl3(O)Re{O2P(1,2,3Tz1-benz)3}Re(O)Cl2]- are formed as the result of a first hydrolysis step of the phosphine oxides, which has been proven by an experiment with H218O. Two more metal-containing products of these reactions, [ReOCl3{O2P(1,2,3Tz1-Ph)2}]- and [Cl3(O)Re{O2P(1,2,3Tz1-benz)2}Re(O)Cl3]-, could also be isolated and studied by X-ray diffraction. Their structures confirm a metal-mediated P-C bond cleavage and the formation of arylphosphinic acids, which finally act as ligands in the products.