New chiral o-hydroxyphenyl diazaphospholidine oxide. Catalytic application in asymmetric addition of diethylzinc to aromatic aldehydes

Article abstract of DOI:10.1016/S0040-4039(98)00388-8

Synthesis of diastereomerically pure o-hydroxyphenyl diazaphospholidine oxide 2 was achieved from a chiral diamine derived from (S)-proline. This new compound has been tested as catalyst in the asymmetric addition of diethylzinc to aromatic aldehydes. Corresponding sec-alcohols were obtained in high yields (up to 90%) with enantiomeric excesses varying from 15 to >99%. The influence of the solvent and also the important relation existing between the nature of the aldehydes and the enantioselectivity have been investigated.