Palladium metal catalysts in Heck C-C coupling reactions

This review is devoted to the application of palladium metal catalysts to t he Heck reaction (arylation or vinylation of alkenes with aryl or vinyl hal ides and pseudohalides). The number of relevant articles published in recen t years shows steadily increasing interest in this field. A brief outline o f the historical development of heterogeneous catalysis as applied to the H eck reaction is given (Section 2). Both supported metal catalysts (Section 3) and stabilized colloidal palladium catalysts (Section 4) are included. H eterogeneous catalysts supported over different kinds of supports (carbon, inorganic oxides, molecular sieves, polymeric materials, etc.) are reviewed under separate headings. Particular attention is paid to the metal leachin g and the nature of catalysis, two tightly connected problems which appear to be still controversial (Section 5). Some perspectives are shortly discus sed in the final section (Section 6). (C) 2001 Elsevier Science B.V. All ri ghts reserved.