铑催化剂的制备及其催化取代苯乙炔不对称聚合研究

The Asymmetric Polymerization of Substitued Phenylacetylene by the Preparation of Rhodium Catalysts

以1,5-环辛二烯(cod)和2,5-降冰片二烯(nbd)为配体,合成了[Rh(cod)Cl]_2和[Rh(nbd)Cl]_2两种铑催化剂,利用红外吸收光谱、核磁共振对其进行测试表征,准确确定其结构,且[Rh(nbd)Cl]_2的收率高达79.4%。再用四种手性氨作为助催化剂和[Rh(cod)Cl]_2或[Rh(nbd)Cl]_2形成催化体系催化含十二烷基的取代苯乙炔单体(1)聚合,聚合物重均分子量最高达49.39万,按照螺旋选择聚合机理诱起了聚合物主链上的螺旋结构;此外,首次在无助催化剂的作用下,用[Rh(nbd)Cl]_2催化含有L-丙氨醚、L-缬氨醚、L-苯丙氨醚取代基的苯乙炔单体(2、3、4)进行不对称聚合,三种聚合物产率高且分子量大,通过自配位螺旋选择聚合诱起三大分子主链上的螺旋结构,所得聚合物Poly(2)、Poly(3)、Poly(4)的主链顺式构型所占百分比分别为70%、77%、77%,因此取得了比较理想的催化效果。

Two kinds of RH catalysts[Rh（cod）Cl]2 and[Rh（nbd）Cl]2 were synthesized with 1,5-cyclooctadiene（cod） and 2,5-norbornadiene（nbd） as ligands, using infrared absorption spectroscopy and nuclear magnetic resonance to characterize them, accurately determined the structure, and[Rh（nbd）Cl]2 yielded up to 79.4%. With four kinds of chiral ammonia as cocatalyst and[Rh（cod）Cl]2 or[Rh（nbd）Cl]2 formed catalytic system to polymerize the substituted phenylacetylene monomer（1） that containing dodecyl, according to the helical selective polymerization mechanism induced the chain helical structure of polymer and the weight-average molecular weight up to 493.9 thousand; In addition,[Rh（nbd）Cl]2 catalyzed substituted phenylacetylene mononer（2,3,4） that contanis L-propane ammonia ether, L-valerian ammonia ether, and L-styrene acrylic ammonia ether for asymmetric polymerization under the action of no cocatalyst for the first time, the yield and molecular weight of three kinds of polymer are both high, in accordance with the helical selective polymerization of the ligand induced helical structure of three macromolecule main chain, and the main chain cis configuration of Poly（2）, Poly（3） and Poly（4） is 70%, 77% and 77% respectively, thus achieved ideal catalytic effect.