Graphical A dynamic double kinetic resolution (DDKR) strategy under the co-catalysis of Raney nickel and Candida antarctica lipase B (CAL-B) was established for the one-pot simultaneous resolution of primary amines and secondary alcohols. Herein, we have established a dynamic double kinetic resolution (DDKR) strategy under the co-catalysis of Raney nickel and Candida antarctica lipase B (CAL-B) for the one-pot simultaneous resolution of primary amines and secondary alcohols (or esters). The DDKR strategy was successfully applied to the resolution of a series of racemic amines and secondary alcohols (or esters) as well as mexiletine, an important antiarrhythmic agent. The catalysts could be recycled and reused several times with the same high activity. Scale-up experiments were also successful. As a more atom-economical and efficient process than traditional simple kinetic resolutions, the DDKR strategy can be widely used to prepare optically pure amines and alcohols.
Dunchi Xiao,Xinzhu Jin,Yuanyuan Song,Yu Zhang,Xun Li,Fei Wang
Proanthocyanin (PA) dimers isolated from Acacia mearnsii bark were enzymatically acylated with palmitic acid as the acyl donor by immobilized Candida antarctica lipase on acrylic resin (Novozym 435). The acylation reaction conditions were optimized by comparing the amount of enzyme, the temperature, the reaction solvents, initial water content, substrate molar ratios and reaction time. The highest acylation conversion of 96.53% was achieved under the follow conditions: PA dimers/palmitic acid at a molar ratio of 1꞉10 in tert-amyl alcohol; initial water content of 5% at 60 °C for 12 h with 30 g/L enzyme dosage. Introducing palmitic acid into PA dimers significantly improved both the lipophilicity and antioxidant properties. The 1-octanol/water partition coefficient of the PA dimers and their derivatives showed that the lipophilicity of the derivatives were 2.4 times higher than that of the PA dimers. The derivatives exhibited strong antioxidant scavenging capacities, approximately 1.6 times greater than the original dimers. This work is of great significance to expand the application of natural PA dimers in cosmetic and food industries and also lay a foundation for the high value-added utilization of A. mearnsii .
危险品化学品经营许可证（带存储）