Resolution of homoallylic alcohols containing dithioketene acetal functionalities. Synthesis of optically active γ-lactones by a combination of chemical and enzymatic methods

Article abstract of DOI:10.1021/jo00099a036

Racemic homoallylic alcohols 1-3 containing dithioketeneacetal functionalities were prepared by addition of aldehydes to the allylic anions of ketene dithioacetals or 2-alkenyl-1,3-dithiane in a regio- and stereoselective manner. Lipase-catalyzed hydrolyses of the corresponding acetates 7-9 afforded optically active alcohols 1-3, which were treated with mercuric chloride to give γ-lactones such as natural hop lactone, whiskey lactone, and cognac lactone.