Synthesis of Main-Chain Ionic Polymers of Chiral Imidazolidinone Organocatalysts and Their Application to Asymmetric Diels-Alder Reactions
作者:Naoki Haraguchi、Nagisa Takenaka、Aisyah Najwa、Yuta Takahara、Mah Kar Mun、Shinichi Itsuno
DOI:10.1002/adsc.201701016
日期:2018.1.4
Main‐chain ionic polymers incorporating chiral imidazolidinone moieties in the polymer main chain were successfully synthesized by the polyaddition reaction of a chiral imidazolidinone dimer with a disulfonic acid. The organocatalytic activities of these polymers were investigated in the asymmetric Diels–Alder reaction between trans‐cinnamaldehyde and 1,3‐cyclopentadiene. The catalytic performance
通过手性咪唑烷酮二聚体与二磺酸的加聚反应,成功合成了在聚合物主链中包含手性咪唑烷酮部分的主链离子聚合物。在反式肉桂醛和1,3-环戊二烯之间的不对称Diels-Alder反应中研究了这些聚合物的有机催化活性。发现聚合物的催化性能对二磺酸酯单元和咪唑烷酮二聚体的化学结构敏感。使用这些非均相聚合手性有机催化剂,对内的对映选择性高达99%获得异构体。该结果高于在均相溶液中用相应的单体和二聚体对应物获得的结果。回收聚合物手性有机催化剂并重复使用数次,以保持其高对映选择性。