Palladium-catalyzed arylation of ethylene. A synthetic route to styrenes, stilbenes, and poly(phenylene vinylene)s

Abstract Palladium-catalyzed arylation of ethylene (the Heck reaction) was studied using (chlorobenzene)Cr(CO) 3 complexes (I) and dibromobenzenes (II). At 100°C styrenes and divinylbenzenes were the major products and stilbenes, and oligo- and poly(phenylene vinylene)s were not formed in the range from 2 to 40 atm of ethylene pressure. At 140°C the polymeric products were formed in low yields. Two-step strategy, which includes coupling reactions of dihalobenzenes with ethylene and subsequently with divinylbenzenes, was successful in yielding poly(phenylene vinylene)s (PPVs).