The Sulfur Rich Fluorothiophosphate Dianions [S5P2F2](2-) and [S3PF](2-) : Cluster and Chelation Control of P-S Heterolysis

The sulfur rich difluoropentathiodiphosphate dianion [S5P2F2](2-), from fluoride addition to P4S10, has a somewhat checkered history and proves to be the main product of the reaction in acetonitrile. Its optimized synthesis, and structural characterization, as either a tetraphenylphosphonium or a tetrapropylammonium salt, [(NPr4)-Pr-n](2)[S5P2F2] allows for the first coordination chemistry for this dianion. Reactions of [S5P2F2](2-) with d(10) metal ions of zinc(II), and cadmium(II), and d(9) copper(II) resulted in a surprising diverse array of binding modes and structural motifs. In addition to the simple bis-chelate coordination of [S5P2F2](2-) with zinc, cleavage of the P-S bond resulted in complexes with the unusual [S3PF](2-) fluorotrithiophosphate dianion. This was observed in two cluster complexes: a trinuclear cadmium complex with mixed [S5P2F2](2-)/[S3PF](2-) ligands, [Cd-3(S5P2F2)(3)(S3PF)(2)](4-) as well as an octanuclear copper cluster, [Cu-8(S3PF)(6)](4-) which form rapidly at room temperature. These new metal/sulfur/ligand clusters are of relevance to understanding multimetal binding to metallothionines, and to potential capping strategies for the condensed nanoparticulate cadmium chalcogenide semiconductors CdS and CdSe.