化学的手法による酵素反応制御を利用する有機合成

抄録

We have demonstrated that chemical efficiency of biocatalysts mediated reactions could be improved by several chemical methodologies. Herin, I report the results focus to three topics: (1)Design of building blocks for organic synthesis via yeast-mediated asymmetric reduction of ketones. (2)Synthesis of chiral gem-difluorocyclopropanes using lipase-catalyzed reaction and linker-oriented design of binaphthol derivatives for optical resolution using lipase-catalyzed reaction. (3)Innovation of lipase-catalyzed reactions by the use of ionic liquids solvent system. We have succeeded in showing that activation of lipase-performances has been accomplished by the coating of enzyme with alkyl PEG ionic liquid. Furthermore, a rational design of phosphonium ionic liquid for ionic liquid coated-lipase (IL1-PS)-catalyzed reaction has been investigated, and very rapid transesterification of secondary alcohols accomplished when IL1-PS was used as catalyst in 2-methoxyethoxymethyl(tri-n-butyl)phosphonium bis(trifluoromethanesulfonyl)amide ([P_444MEM] [NTf₂]) as solvent while perfect enantioselectivity was maintaining. Increased K_cat value was suggested to be the most important factor in IL1-PS working the best in [P_444MEM] [NTf₂] solvent.