FACILE PREPARATION OF NOVEL NONRACEMIC OXY-SUBSTITUTED CYCLOPROPANONES,S-ACETALS BY GAMMA-CYCLIZATION OF GLYCERIC ALDEHYDE DITHIOACETAL DERIVATIVES AND STUDIES OF THEIR REACTIVITY

Easily available glyceric aldehyde dithioacetals, (R)-1 and (R)-2, are converted via their tosylates, (R)-7a and b, and gamma-elimination in to nonracemic oxy-substituted cyclopropanone S,S-acetals, (R)-12 and ( R)-13, in the presence of suitable electrophiles for trapping of alkox ide intermediates. Treatment of cyclopropanol (R)-14 with Burgess' rea gent causes no 1,2-elimination, but a remarkable S-N etherification wi th retention of configuration.