Mathematical Modelling of Lipase Catalysed Resolution ofO-Acetyl andO-Formyl Derivatives of Secondary Alcohols

Abstract
Lipase catalysed transesterification of O-acetyl and O-formyl derivatives of several sterically hindered secondary alcohols with n-butanol is studied. The reaction is mathematically modelled and the rate constants in the model are evaluated by transient parameter estimation procedure. Several models are considered for predicting the enantiomeric excess (ee) of the product and compared with experimental observations. It is found that the maximum ee depends only on the rate constants of the two competing reactions and not on the order of reaction. A second order model is found to predict the observed behaviour well. When the data is fitted to an equilibrium type of model developed by Chen et al. (1987), it is found that the rate of forward reaction is several orders of magnitude larger than the rate of reverse reaction. The effect of acetyl and formyl groups on the reactivity and selectivity are also discussed.