Preparation of stereoisomers of 3-sulfinylbutyric acid from (R)- and (S)-4-methyl-2-oxetanone

Article abstract of DOI:10.1055/s-1992-34181

The β-lactone ((S) and (R)-4-methyl-2-oxetanone, 1, ent-1), readily available from (R)- and (S)-3-hydroxybutyric acid, is opened by sodium hydrosulfide, sodium alkane- and arenethiolates, respectively, with inversion of configuration. The resulting 3-(alkylthio)-2f, 2g, and 3-(arylthio)butyric acids, 2b-2e, ent-2h-2k (Table 1), oxidized with hydrogen peroxide in acetone to give the corresponding 3-(alkylsulfinyl)- and 3-(arylsulfinyl)butyric acids as mixtures of diastereoisomers 3b-3k and 4b-4k. These are separated and the pure like and unlike diastereoisomers isolated and fully characterized (Table 4). Configurational assignments rest upon a crystal structure analysis and comparison of properties in the two series.