Ks. Chu et Jp. Konopelski, SELF-REPRODUCTION OF CHIRALITY - ASYMMETRIC-SYNTHESIS OF BETA-ALKYL-BETA-AMINO ACIDS FROM ENANTIOMERICALLY PURE DIHYDROPYRIMIDINONES, Tetrahedron, 49(41), 1993, pp. 9183-9190
Enantiomerically pure heterocycle 2 is deprotonated at C6 with tert-bu
tyllithium at -78-degrees-C. The resulting carbanion reacts with alkyl
halides and aldehydes to give the corresponding alkylated products. R
eduction of the double bond followed by hydrolysis affords enantiomeri
cally pure beta-alkyl-beta amino acids.