ChemInform Abstract: Asymmetric Synthesis Using Chiral Piperazine. Part 1. Asymmetric Synthesis of 2-Substituted Alcohol and Carboxylic Acid by Diastereoselective Alkylation of Chiral Diamides Derived from Piperazines.

ChemInform Abstract

The chiral auxiliary (I) is employed for the transformation of (II) to (VI), (VII) and (IX). While alkylation of (IIIa) with (IV) and subsequent reduction yields the (S)-isomers (VI), the alternative procedure using (IIIb) and (VIII) gives either (S)-(VIa) or its enantiomer (R)-(IX) as the major product, depending upon wether an additive such as HMPA is added or not.