Stereocontrol in the Addition of Allyl Metal Reagents to an Optically Active Imine Derived from Malic Acid, Leading to a Formal Synthesis of (+)-Negamycin

Complete anti-stereoselection has been achieved on the addition of allyl metal reagents to an optically active imine derived from malic acid. The homoallyl amine thus obtained was converted into the known intermediate for the synthesis of (+)-Negamycin in enantiomerically pure form.