Palladium(II)-Catalyzed Alternating Copolymerization of Allene with Carbon Monoxide and the Synthesis of Terpolymer with Alt-Allene-Carbon Monoxide and Alt-Ethene-Carbon Monoxide Blocks.

摘要

The alternating copolymerization of 3 3-dimethylallene with carbon monoxide was achieved using [Pd(PPh_3)_2(MeCN)_2](BF_4)_2 as the catalyst. The use of bidentate phosphines resulted in drastically reduced yields. In order to gain insight into the copolymerization mechanism, the stepwise successive insertions of 3, 3-dimethylallene And carbon monoxide into palladium-carbon nonds in the complexes, Pd(PPh_3)_2(Me)(Cl), [Pd(PPh_3)_2(C(O)- C_6H_4-Me-p)(MeCN)](BF_4), and [Pd[(Dppp)(Me)(MeCN)](BF_4) (Dppp: 1, 3-bis(diphenylphosphino)propane), were Studied.