Chiral synthesis of secondary alcohols using Geotrichum candidum
Kaoru Nakamura1, Tomoko Matsuda, Tadao Harada
1Institute for Chemical Research, Kyoto University, Kyoto, Japan. nakamura@scl.kyoto-u.ac.jp
Abstract:
Chiral synthesis of secondary alcohols of both the (S)- and (R)-enantiomer with extremely high enantioselectivities (up to >99% ee) using a biocatalyst, Geotrichum candidum, is reviewed. Resting cell and dried-cell preparation using acetone were applied to oxidation, reduction, and deracemization reactions. Many methods to improve the reactivity and enantioselectivity of the reactions were developed. For example, additives such as secondary alcohols and hydrophobic resin (Amberlite XAD) were used in nonaqueous reaction media such as organic and supercritical solvents as well as in aqueous ones. As a result, optically pure alcohols of both enantiomers were synthesized on a gram scale.
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