A FACILE ASYMMETRIC SYNTHESIS OF β-SUBSTITUTED ALKANOIC ACID. THE HIGHLY STEREOSELECTIVE MICHAEL ADDITION OF GRIGNARD REAGENTS TO α,β-UNSATURATED CARBOXYLIC AMIDES DERIVED FROM L-EPHEDRINE

Article abstract of DOI:10.1246/cl.1981.913

The Michael addition of Grignard reagents to chiral α,β-unsaturated carboxylic amides derived from l-ephedrine affords highly optically active β-substituted alkanoic acids after acid hydrolysis.This high stereoselectivity is explained by considering the formation of rigid internal chelate complexes.