Sequential Kinetic Resolution of (+/-)-2,3-Butanediol in Organic Solvent Using Lipase From Pseudomonas cepacia.

Article abstract of DOI:10.1016/S0957-4166(00)82248-X

Lipase from Pseudomonas capacia (PCL, Amano PS) catalyzed the enantioselective diacetylation of (+/-)-2,3-butanediol in vinyl acetate.Both acetylation steps favored the (R)-enantiomer (E₁ = 12, E₂ = 34), thus the reaction is a sequential kinetic resolution.The enantioselectivities of the two steps reinforced one another because both steps proceeded at comparable rates (S = 3) yielding an overall enantioselectivity of approximately 200.A synthetic-scale resolution starting from 2.7 g of (+/-)-2,3-butanediol yielded the diacetate ester of (R)-(-)-butanediol with 96percent ee (1.6 g, 30percent yield) and (S)-(+)-butanediol with 99percent ee (0.63 g, 23percentyield).This preparation is carried out entirely in organic solvent, thereby avoiding the difficult and low yield extraction of 2,3-butanediol from aqueous solution.