Mechanistic Rationale of a Palladium-Catalyzed Allylic Substitution Polymerization—Carbon−Carbon Bond-Forming Polycondensation out of Stoichiometric Control by Cascade Bidirectional Allylation

The reactions of transient olefin–LnPd0 complexes must be controlled for successful allylic-substitution polymerization. These reactions reveal a novel aspect of C−C bond-forming polycondensation (see scheme).