913962-59-1Relevant articles and documents
(S,S)-(+)-pseudoephedrine as chiral auxiliary in asymmetric conjugate addition and tandem conjugate addition/α-alkylation reactions
Reyes, Efraim,Vicario, Jose L.,Carrillo, Luisa,Badia, Dolores,Uria, Uxue,Iza, Ainara
, p. 7763 - 7772 (2007/10/03)
(Chemical Equation Presented) Organolithium reagents undergo highly regio- and diastereoselective 1,4-addition to (S,S)-(+)-pseudoephedrine enamides furnishing the corresponding β-alkyl-substituted adducts in excellent yields and diastereoselectivities. In addition, the intermediate lithium enolates generated after the conjugate addition step undergo a highly diastereoselective alkylation reaction, furnishing α,β-dialkyl- substituted amides in high yields. The obtained adducts have been converted into chiral nonracemic β-alkyl- and α,β-dialkyl-substituted carboxylic acids and γ-alkyl- and β,γ-dialkyl-substituted alcohols using very simple and high-yielding procedures.