Solid-supported cross-coupling catalysts derived from homogeneous nickel and palladium coordination complexes

Abstract

Solid-supported catalysts derived from homogeneous nickel(II) and palladium(II) non-symmetrical salen-type coordination complexes have been prepared and shown to be effective in the heterogeneous catalysis of carbon–carbon cross-coupling reactions. The nickel catalyst has been used in room-temperature Tamao–Kumada–Corriu reactions and the palladium catalyst in the Heck reaction at elevated temperatures. The complexes were prepared by improved methods and characterised by spectroscopic techniques. Comparisons between the solid-supported catalysts and their homogeneous analogues are reported. The single-crystal structure determination of the nickel and palladium complexes [M(salenac-OH)] [M = Ni, Pd; salenac-OH = 9-(2′,4′-dihydroxyphenyl)-5,8-diaza-4-methylnona-2,4,8-trienato](2−)] is reported.