Olefin Insertion into a Pd-F Bond: Catalyst Reactivation Following β-F Elimination in Ethylene/Vinyl Fluoride Copolymerization.

The discrete (phosphinoarenesulfonate)Pd fluoride complex (POBp,OMe )PdF(lutidine), where POBp,OMe =(2-MeOC6 H4 )(2-{2,6-(MeO)2 C6 H3 }C6 H4 )(2-SO3 -5-MeC6 H3 )P, inserts vinyl fluoride (VF) to form (POBp,OMe )PdCH2 CHF2 (lutidine) and inserts multiple ethylene (E) units to generate polyethylene that contains -CH2 F chain ends. These results provide strong evidence that the -CHF2 and -CH2 F chain ends in E/VF copolymer generated by (phosphinoarenesulfonate)PdR catalysts form by β-F elimination of Pd(β-F-alkyl) species, VF or E insertion of the resulting (PO)PdF species, and subsequent chain growth. These results also imply that β-F elimination is not an important catalyst deactivation reaction in this system.