Synthesis of the (1 S,2 S)- and (1 R,2 S)-stereoisomers of the respective E- and Z-isomers of ethyl 4-[(2-hydroxycyclohexyl)methyl]phenoxy-3-methyl-2-butenoate using yeast whole cell bioreduction of the parent ketones

Abstract

Saccharomyces cerevisiae, strain DBM 2115, was successfully employed in the reduction of the separated Z- and E-isomers of ethyl 4-[(2-oxocyclohexyl)methyl]phenoxy-3-methyl-2-butenoates 1 and 2, in order to prepare the (1 S,2 S)- and (1 R,2 S)-enantiomers of the corresponding ethyl 4-[(2-hydroxycyclohexyl)methyl]phenoxy-3-methyl-2-butenoates 3– 6. The products were obtained with the required absolute configuration: (1 S,2 S)- 3 (ee = 98%; yield 48%), (1 R,2 S)- 4 (ee = >99%; yield 45%), (1 S,2 S)- 5 (ee = 98.5%; yield 47%), and (1 R,2 S)- 6 (ee = >99%; chemical yield 44%).