Synthesis and characterization of new Cu(I) complexes of tetramethyldiphosphine disulfide and resolution of the controversy regarding the corresponding Cu(II) complexes

WOS: 000166507700009The controversy as to whether or not the copper(II) complexes (CuX2 .L) [X = Cl or Br, L = tetramethyldiphosphine disulfide (tetramethyl-1,2-dithioxodi-lambda (5)-phosphane)] were actually isolated by a group of researchers in the late 1960s has now been settled. It has been shown that these two complexes could not have been obtained at the preparative conditions mentioned. It has been established by elemental analyses, IR, far-IR, Raman and XRD data that the confusion stemmed, at least partially, from the coexistence of two stoichiometrically and structurally different copper(I) complexes, the previously reported (CuX.L)(2) (X = Cl or Br) and the hitherto unknown ([)(CuX)(2).L](n) (X = Cl or Br), whose relative amounts depend upon the temperature and the water content of the solvent used. Spectroscopic evidence suggests that the new complexes are in a polymeric step structure in which both the halogen atoms and the ligand molecules are bridging