Pseudomonas sp. Lipase Immobilized on Magnetic Porous Polymer Microspheres as an Effective and Recyclable Biocatalyst for Resolution of Allylic Alcohols

Magnetic porous polymeric microspheres containing epoxy groups were prepared by suspension polymerization (denoted as magnetic Fe 3 O 4 @GEM microspheres). Fe 3 O 4 @GEM with a specific surface area of 30.41 m 2 /g, average pore diameter of 17.13 nm, and pore volume of 0.13 cm 3 /g exhibited superparamagnetic behavior with the saturation magnetization of 7.1 emu/g. The content of epoxy groups on Fe 3 O 4 @GEM was 0.22 mmol/g. Pseudomonas sp. lipase (PSL) was covalently immobilized onto the Fe 3 O 4 @GEM microspheres through the reaction between the amino groups of the enzyme and the epoxy groups on the microspheres. PSL/Fe 3 O 4 @GEM exhibited enhanced enantioselectivity for the resolution of allylic alcohol to the corresponding optically active ( S )‐allylic alcohol and ( R )‐allylic alcohol acetate compared to free PSL. The enantiomeric excess of ( S )‐l‐pheny‐2‐propen‐1‐ol for the former (98.1%) was 81.7 times that of the latter (1.2%) when the immobilized PSL was used for transesterification resolution of ( R , S )‐l‐pheny‐2‐propen‐1‐ol. Furthermore, the ee s and ee p values were still retained at 95.2% and 95.4% after PSL/Fe 3 O 4 @GEM was recycled 10 times, indicating that PSL/Fe 3 O 4 @GEM had very good reusability. In addition, the transesterification resolution of ( R , S )‐1‐(4‐methylphenyl)‐2‐propen‐1‐ol and ( R , S )‐1‐(4‐bromophenyl)‐2‐propen‐1‐ol was catalyzed by PSL/Fe 3 O 4 @GEM, affording ideal ee s and ee p values of 99.3%, 97.4% and 99.6%, 98.2%, respectively. Therefore, PSL/Fe 3 O 4 @GEM demonstrated its potential as a highly efficient enzymatic reactor and Fe 3 O 4 @GEM would be very promising carriers for immobilizing enzymes in industrial application.