INVESTIGATIONS ON THE CORRELATION BETWEEN STRUCTURAL, REDOX, AND PHOTOCHEMICAL PROPERTIES OF COPPER(II) THIOLATE COMPLEXES

Schiff bases synthesized from appropriate diamines and 4-benzoyl-3-met hyl-pyrazoline-5-thion form stable copper(II) thiolate complexes. The coordination sphere of these complexes is slightly tetrahedrally disto rted. The dihedral angle between both CuNS-planes ranges from 3.3 degr ees(1) to 9.0 degrees(2). The complexes 1-4 form strongly coloured cat ions 1(+)-4(+)-upon electrochemical as well as photochemical oxidation in chlorinated solvents. These complex cations are sufficiently stabl e, thus allowing their investigation at 193 K. Electrochemical oxidati on at 293 K and continuous photolysis in chlorinated solvents lead to the formation of colourless secondary products.