摘要
We report an efficient kinetic resolution of racemic 2-(4-chlorophenyl)-4-hydroxytetrahydro-pyran (CLP-4-HTHP) via Pseudomonas cepacia lipase (PSL)-catalyzed transesterification, where PSL is immobilized on a core-shell MnFe204@SiO2-(CH2)3-NH2 carrier and used as a magnetically separable catalyst. The as-synthesized PSL/MnFe204@SiO2-(CH2)3-NH2 catalyst exhibits enhanced catalytic activity for resolving racemic CLP-4-HTHP to the corresponding optically pure (2R,4S)-CLP-4-HTHP compared to the free PSL. The ees for the former is 2.3 times larger than that for the latter under optimized conditions (99.4% and 44.1%, respectively), although the eep for them are same (99.2%). Meanwhile, the PSL/MnFe204@SiO2-(CH2)3-NH2 catalyst possesses a high saturate magnetization of 59.7 emu/g and could be easily recovered by magnetic separation and reused. The catalytic activity in six recycling tests did not significantly decrease, suggesting its great potential for industrial applications.
We report an efficient kinetic resolution of racemic 2-(4-chlorophenyl)-4-hydroxytetrahydro-pyran (CLP-4-HTHP) via Pseudomonas cepacia lipase (PSL)-catalyzed transesterification, where PSL is immobilized on a core-shell MnFe204@SiO2-(CH2)3-NH2 carrier and used as a magnetically separable catalyst. The as-synthesized PSL/MnFe204@SiO2-(CH2)3-NH2 catalyst exhibits enhanced catalytic activity for resolving racemic CLP-4-HTHP to the corresponding optically pure (2R,4S)-CLP-4-HTHP compared to the free PSL. The ees for the former is 2.3 times larger than that for the latter under optimized conditions (99.4% and 44.1%, respectively), although the eep for them are same (99.2%). Meanwhile, the PSL/MnFe204@SiO2-(CH2)3-NH2 catalyst possesses a high saturate magnetization of 59.7 emu/g and could be easily recovered by magnetic separation and reused. The catalytic activity in six recycling tests did not significantly decrease, suggesting its great potential for industrial applications.
基金
financially supported by the National Natural Science Foundation of China (Nos. 21064005 and 21263020)
the National Basic Research Program 973 (No. 2012CB723106)