Resolution and absolute configuration of some α-aminoacetals: en route to enantiopure N-protected α-aminoaldehydes

Abstract

The first successful resolution of rac-α-aminoacetals via diastereoisomeric salt formation with optically pure N-protected aminoacids is reported. The absolute configuration assignment of α-aminoacetal enantiomers is performed by an entirely non-racemizing chemical correlation method involving N-protection and a new efficient hydrolysis step followed by a reduction of the resulting N-protected α-aminoaldehyde intermediates. A racemization method of optically enriched α-aminoacetals is exemplified to allow valorisation of both enantiomers.