Related Experiment Video
Updated: Aug 8, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Tandem asymmetric conjugate addition/alpha-alkylation using (S,S)-(+)-pseudoephedrine as chiral auxiliary
Efraim Reyes1, Jose L Vicario, Luisa Carrillo
1Departamento de Química Organica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco-Euskal Herriko Unibertsitatea, P.O. Box 644, E-48080 Bilbao, Spain.
Abstract:
Alpha,beta-unsaturated amides derived from the chiral amino alcohol (S,S)-(+)-pseudoephedrine undergo a very clean and diastereoselective tandem conjugate addition/alpha-alkylation reaction. Excellent results have been achieved using a wide range of differently substituted conjugate acceptors, organolithium reagents, and alkyl halides. The chiral auxiliary could be easily removed from the obtained adducts by reduction, furnishing chiral nonracemic alpha,beta-branched alcohols in a very easy and efficient way. [reaction: see text]
Related Concept Videos
SN2 Reaction: Stereochemistry
If the substrate is an achiral molecule at the α-carbon, the inversion of configuration is not observed.
Prochirality
Radical Anti-Markovnikov Addition to Alkenes: Overview
Chirality at Nitrogen, Phosphorus, and Sulfur
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
Conjugate Addition to α,β-Unsaturated Carbonyl Compounds
Preparation of Alkynes: Alkylation Reaction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
