Crystal structure of bis(1,1,2,2-tetramethyldiphosphane-1,2-dithione-κ2S,S′)copper(I) tetrafluoridoborate

In the title compound, [Cu(C4H12P2S2)2]BF4, both diphosphine disulfide molecules bind to the CuI atom, as chelating ligands via the S atoms, forming a monovalent cation with a slightly distorted tetrahedral coordination around the CuI atom. The average Cu—S distance is 2.350 (15) Å, with small but possibly significant differences within each chelate ring. Ligand P=S distances average 1.964 (3) Å, and the P—P distances are 2.2262 (13) and 2.2166 (14) Å. The ligand chelate rings are twisted in opposite directions, with one in the λ and one in the δ configuration. Although the anisotropic displacement parameters of the F atoms of the anion are quite large compared to that of the B atom, difference Fourier syntheses indicate only one set of sites for the F atoms. In the crystal, possible C—H...F hydrogen bonds may stabilize the orientation. The B—F distances, uncorrected for libration, average 1.359 (6) Å