EFFECT OF ALCOHOLS ON THE PHOTOCHEMICAL-REACTION OF BIS(N,N'-DIETHYLDITHIOCARBAMATO)COPPER(II) IN CHCL3

Bis(N,N'-diethyldithiocarbamato)copper(II) (Cu(Et(2)dtc)(2)) is initia lly photoreduced to Cu-I within its donor-acceptor (DA) complex with C HCl3 and the quantum yields obtained are independent of the compositio n of the CHCl3-EtOH solvent mixture. Two intermediate copper(II) compl exes are subsequently formed in equilibrium, in a dark reaction of the primary photoproduct with CHCl3, when Cu(Et(2)dtc)(2) photolysis is c arried out in CHCl3-EtOH (150:1 to 50:1). These are the monomeric spec ies Cu-II(Et(2)dtc)Cl and its chloride-bridged dimeric form Cu-2(Et(2) dtc)(2)Cl-2. The latter is the only intermediate Cu-II complex obtaine d in pure CHCl3. A reaction mechanism is proposed and the role of alco hol is discussed from a combined analysis of spectrophotometric and el ectron paramagnetic resonance (EPR) data.