EPR study on the ligand-exchange reaction between bis(diethyldiselenocarbamato)copper(II) and bis(octyldithiocarbonato)copper(II)

EPR study on the ligand-exchange reaction between bis(diethyldiselenocarbamato)copper(II), Cu(Et 2 dsc) 2 , and bis(octyldithiocarbonato)copper(II), Cu(octxant) 2 , in CH 2 Cl 2 , CHCl 3 , CCl 4 , C 6 H 6 and C 6 H 5 ·CH 3 is reported for the first time. Mixing of equimolar amounts of the parents (chromophores CuSe 4 and CuS 4 , respectively) in C 6 H 6 , C 6 H 5 ·CH 3 and CH 2 Cl 2 makes EPR signals of both parents superimposed by the spectrum of a mixed-chelate Cu(xant)(dsc) complex (chromophore CuS 2 Se 2 ). A new additional EPR spectrum appears in CHCl 3 or CCl 4 due to a five-coordinate mixed-ligand complex with the chromophore Cu(S 3 Se)S as follows by comparing the g -values of parents and mixed-ligand complexes. The appearance of this complex could be explained having in mind donor–acceptor properties of complexes, solvents and the resultant reaction of Cu(octxant) 2 with the ester of diselenocarbamic acid yielded in Cu(Et 2 dsc) 2 destruction by CCl 4 or CHCl 3 .