首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Asymmetric anionic polymerization of maleimides bearing bulky substituents
Authors:Tsutomu Oishi  Kenjiro Onimura  Yukio Isobe  Hiroaki Yanagihara  Hiromori Tsutsumi
Abstract:Asymmetric anionic homopolymerizations of N‐substituted maleimide (RMI) bearing bulky substituents R = benzyl, diphenylmethyl (DPhMI), 9‐fluorenyl (9‐FlMI), triphenylmethyl, (diphenylmethyloxycarbonyl)methyl, (9‐fluorenyloxycarbonyl)methyl] were carried out with complexes of organometal compounds (alkyllithium, diethylzinc) with six chiral ligands to obtain optically active polymers. The chiroptical properties of the polymers were affected strongly by the substituents on nitrogen in the maleimide ring, the organometal and chiral ligands. Poly(DPhMI) initiated by an n‐butyllithium/(−)‐sparteine (Sp) complex showed a positive specific rotation (α]urn:x-wiley:0887624X:media:POLA5:tex2gif-stack-1 +60.3°). Poly(9‐FlMI) prepared with a florenyllithium/Sp complex exhibited the highest specific rotation (+65.7°). The specific rotations of the poly(RMI) obtained were attributed to different contents between the stereogenic centers (S,S) and (R,R) based on threo‐diisotactic structures of the main chain. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 310–320, 2000
Keywords:N‐substituted maleimide  asymmetric polymerization  bulky substituent  optically active polymer  anionic polymerization
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号