Chinese Journal of Catalysis ›› 2012, Vol. 33 ›› Issue (3): 473-477.DOI: 10.1016/S1872-2067(11)60345-8

• Research papers • Previous Articles     Next Articles

A Poly(hydroxyethyl methacrylate)-Immobilized Chiral Manganese(III)salen Catalyst for Asymmetric Epoxidation of α-Methylstyrene

XU Guojin1, WEI Saili2, FAN Yingguo1, ZHU Libo1, TANG Yuhai2,*, ZHENG Yuansuo2   

  1. 1Environment Monitoring Center of Ningbo, Ningbo 315012, Zhejiang, China; 2Institute of Analytical Sciences, School of Science, Xi’an Jiaotong University, Xi’an 710061, Shaanxi, China
  • Received:2011-09-08 Revised:2011-11-22 Online:2012-03-15 Published:2015-07-27

Abstract: Phenylalaninol was introduced in the C5 and C5′ position of a chiral Mn(III)salenCl compound, and the catalyst was then immobilized on poly(hydroxyethyl methacrylate) (pHEMA) by axial coordination. The catalytic system, with (R,R)(R,R)pHEMA-immobilized Mn(III)salenCl as catalyst and [bmim]PF6 as reaction medium, gave excellent catalytic activity and enantioselectivity with 80%–91% ee values and 84%–92% yields for the asymmetric epoxidation of α-methylstyrene. The catalyst can be reused several times without significant loss of catalytic activity. This was due to a chiral synergy between the chiral carbons of the amino alcohol and the chiral carbons of (R,R)-diaminocyclohexane.

Key words: poly(hydroxyethyl methacrylate), immobilized Mn(III)salen, asymmetric epoxidation, α-methylstyrene, ionic liquid