THERMAL AND PHOTOCHEMICAL-REACTIONS OF BIS(8-QUINOLINOLATO) COPPER(II), BIS(8-QUINOLINETHIOLATO)COPPER(II) AND (8-QUINOLINOLATO,8-QUINOLINETHIOLATO)COPPER(II) WITH CHLOROALKANES

The thermal and photochemical reactions of bis(8-quinolinolato) Cu(II) , Cu(ox)(2), bis(8-quinolinethiolato) Cu(II), Cu(tox)(2), and their te rnary complex Cu(ox)(tox) have been studied in CCl4, CHCl3 and CH2Cl2. In CCl4 both S-containing complexes Cu(tox)(2) and Cu(ox)(tox) underg o thermal reactions within their donor-acceptor complexes with CCl4 to yield free tox(.) radical and Cu-I(tox), Cu-I(ox) respectively. On th e time scale of the experiment the reaction does not occur thermally i n CHCl3, and CH2Cl2, but it occurs photochemically in all chloroalkane s. The charge transfer irradiations induce intramolecular oxidation of the ligand and reduction of copper(II) to copper(I) supported by EPR data and UV-Vis spectra of the complexes together with quantum yield r esults. The behaviour of Cu(ox)2 upon short light irradiation is simil ar to that of Cu(tox)(2) and Cu(ox)(tox). Long-term photolysis of Cu(o x)(2) leads to secondary reactions in all chloroalkanes. The study all ows to get some insight into the behaviour of the complexes towards th e acceptor properties of chloroalkanes. (C) 1998 Elsevier Science S.A. All rights reserved.