Addition of 1,3-Benzoxathiole 3-Oxide Anion to Azomethines under Varying Reaction Conditions

Abstract

The reaction of benzoxathiole 3-oxide with LDA in THF gave an anion which was reacted with azomethines under varying conditions of temperature and solvent. At −78 °C in THF, the two diastereomers resulting from a trans addition were mainly obtained, while at temperatures higher than −40 °C, or upon increasing the solvent polarity, only one trans and one cis diastereomer were obtained. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)