Copper (II) chloride-dmf catalytic system in solution and on silica

The connections between composition and formation conditions of catalysts b ased on immobilised complexes of Cu(II) and dmf as precursors and their cat alytic activity in C-CI bond metathesis in system CCl4-n-C10H22 were studie d. High activity and selectivity could be obtained providing that a lamina of dmf containing mononuclear copper complexes forms in pores of a support. It was shown that the composition and structure of surface complexes does not depend on concentrations of copper ions or dmf in precursor solution. T he loss of catalytic activity when the support cannot fix the lamina (e.g., charcoal in contrast with silica) is observed. The key stage of catalysis could be a reduction of Cu(II) to Cu(I). (C) 1999 Elsevier Science B.V. All rights reserved.