[Poly(styryl)phenanthroline]palladium catalyst. Synthesis and some of its applications in vinylic substitution reactions with organic halides

Abstract

A polymer-bound phenanthroline palladium catalyst,

-ph-phen -Pd (reduced), has been synthesized although the precise form of the Pd has not yet been established unambiguously. The catalyst is very stable to air and moisture and can be stored for long periods. It was characterized by IR, DRS, ESCA, electron microscopy, and elemental analysis. The catalyst showed high activity for vinylic substitution reactions of iodobenzene with olefins. In general, smaller amounts of catalyst were used than those in homogeneous reactions, while the yields were about equal or a little higher. The catalyst can be recovered and reused, with tributylamine as the base: however, the catalytic activity was dramatically reduced after three runs as a result of leaching of palladium from the polymer support. Bromobenzene can also be induced to react with styrene using this catalyst in the absence of phosphine ligands.