Diastereo‐ and Enantioselective Synthesis of 1,2‐Amino Alcohols and Protected α‐Hydroxy Aldehydes from Glycol Aldehyde Hydrazones

Abstract

Abstract Starting from chiral glycol aldehyde hydrazones ( S )‐ 2 , we prepared differently protected α‐hydroxy aldehydes ( R )‐ or ( S )‐ 4 as well as N ‐acetyl‐protected 1,2‐amino alcohols ( R )‐ 11 in high enantiomeric excesses via azaenolate α‐alkylation or nucleophilic 1,2‐addition to the CN double bond. The successive introduction of two vicinal stereogenic centres opens a new, flexible syn ‐diastereo‐ and enantioselective route to functionalised, N ‐acetyl‐protected, vicinal amino alcohols ( R,R )‐ 13 , which was demonstrated in the case of the γ‐amino‐β‐hydroxycarboxylic acid statin ( R,R )‐ 15 and its analogues B .