New routes to pentafluorophenyl derivatives with germanium-chalcogen bonds

Tris(pentafluorophenyl)germanethiol, (C₆F₅)₃GeSH (Ia), was obtained in good yield by heating the tris(pentafluorophenyl)germane with elemental sulphur or by the exchange between Et₃GeSH and (C₆F₅)₃GeBr. The reaction between sulphur and (C₆F₅)₂GeH₂ or C₆F₅GeH₃ gives heterocyclic products with chains of alternating germanium and sulphur atoms in the cycles. The compounds (C₆F₅)₃Ge]₂X (X = S, Se) were prepared by exchange reaction of (Et₃Ge)₂X with tris(pentafluorophenyl)germanium bromide and by reaction of chalcogens (S₈, Se₈) with hexakis(pentafluorophenyl)digermane. Ia reacts with diethylmercury affording (C₆F₅)₃GeSHgEt. Insertion of elemental sulphur into the GeHg bond of bistris(pentafluorophenyl)germyl]mercury led to the thermally stable (C₆F₅)₃GeSHgGe(C₆F₅)₃.