No abstract

Lipase-catalyzed transesterification was demonstrated using methyl esters as acyl donors under reduced pressure in an ionic liquid ([bmim]PF6) solvent system. The transesterification of 5-phenyl-1-penten-3-ol took place smoothly under reduced pressure at 27 hPa at 40 °C when methyl phenylthioacetate was used as acyl donor in [bmim]PF6, and we succeeded in obtaining the corresponding acylated compound in optically pure form; this makes it possible to use lipase repeatedly because there was no drop in the reaction rate despite three repetitions of the process.

Enantioselective syntheses Enantioselective syntheses O 0031Lipase-Catalyzed Enantioselective Acylation in a Halogen Free Ionic Liquid Solvent System. -The first successful example of a lipase-catalyzed enantioselective transesterification using imidazolium alkyl sulfate as reaction medium is described.-(ITOH*, T.; OUCHI, N.; HAYASE, S.; NISHIMURA, Y.; Chem. Lett. 32 (2003) 7, 654-655; Dep. Mater. Sci., Fac. Eng., Tottori Univ., Koyama, Tottori 680, Japan; Eng.) -F. Santoso

Lipase-catalyzed enantioselective transesterification was demonstrated using several types of imidazolium alkyl sulfate as a reaction medium. The desired optically pure acetate was successfully obtained under the conditions used, although reaction rate was inferior to that in imidazolium tetrafluoroborate.