Density functional theory has been employed to study the homogeneous catalytic copolymerization of styrene with carbon monoxide. The copolymerization reaction is catalyzed by Pd（II） coordinated with 2,2＇-bipyridine...Density functional theory has been employed to study the homogeneous catalytic copolymerization of styrene with carbon monoxide. The copolymerization reaction is catalyzed by Pd（II） coordinated with 2,2＇-bipyridine, a conventional nitrogen-containing bidentate ligand with achiral C2v symmetry. The chain propagation mechanism for the alternating copolymerization as well as the side reactions, including multiple insertions of CO and homopolymerization of styrene, has been investigated. This study focused exclusively on regioisomerism and stereoisomerism. We have demonstrated that the strictly alternating copolymerization is kinetically and thermodynamically favored over the side reactions （i.e., multiple insertions of CO and homopolymerization of styrene）. The regiochemistry study indicates the 2,1 type. Furthermore, the stereochemistry study shows that the syndiotactic conformation is preferred over the isotactic or atactic conformations.展开更多
基金financially supported by the NSFC(Nos.91127046 and 20974078)KPCME(No.109043)+1 种基金SRFDP (No.200800561006)High Performance Computing Center of Tianjin University,China and National Supercomputer Center in Tianjin,China
文摘Density functional theory has been employed to study the homogeneous catalytic copolymerization of styrene with carbon monoxide. The copolymerization reaction is catalyzed by Pd（II） coordinated with 2,2＇-bipyridine, a conventional nitrogen-containing bidentate ligand with achiral C2v symmetry. The chain propagation mechanism for the alternating copolymerization as well as the side reactions, including multiple insertions of CO and homopolymerization of styrene, has been investigated. This study focused exclusively on regioisomerism and stereoisomerism. We have demonstrated that the strictly alternating copolymerization is kinetically and thermodynamically favored over the side reactions （i.e., multiple insertions of CO and homopolymerization of styrene）. The regiochemistry study indicates the 2,1 type. Furthermore, the stereochemistry study shows that the syndiotactic conformation is preferred over the isotactic or atactic conformations.
