MECHANISM OF ARYLATION AND CARBOMETHOXYLATION OF OLEFINS WITH ORGANOPALLADIUM COMPOUNDS

Phenylation and carbomethoxylation of olefins with “phenyl and carbomethoxylpalladium acetate,” prepared in situ by the exchange reaction of the corresponding mercury compounds and palladium acetate, have been investigated under conditions where the initially formed products are stable. The reactions yield almost completely “anti-Markovnikov” products except with the least substituted (least hindered) olefins, such as propylene, where up to 30% “Markovnikov” addition may occur depending upon the reaction conditions. Substantial amounts of nonconjugated olefins are generally formed depending upon the substituents present. The reactions are quite stereospecific, yielding products expected from a cis-addition of the organopalladium acetate followed by a cis-elimination of hydridopalladium acetate. Minor amounts of unexpected olefin products are seen in some reactions, apparently arising from readdition of the eliminated palladium hydride species in the reverse direction followed by re-elimination of a hydride containing a different hydrogen atom. © 1969, American Chemical Society. All rights reserved.