Polypyrrole-supported graphite felt for Heck reaction in solid phase synthesis

Substrate immobilization on graphite felt for solid phase Heck reaction was achieved by electrochemical polymerization of the substrate precursor containing a pyrrole side chain, where the amount of substrate on the electrode surface was easily controlled by the number of repeated cyclic voltammetric scanning. Couplings between olefins and the 4-iodobenzoic acid-modified graphite felt electrode or aromatic halides and the 4-vinylbenzoic acid-modified graphite felt electrode in the presence of palladium catalyst proceeded smoothly in satisfactory yields. The used substrate-modified electrode was reproduced by the treatment of used electrode with activated ester species of 4-vinylbenzoic acid, and was able to be recycled to Heck reaction in solid phase synthesis.