Homochiral lithium amides for the asymmetric synthesis of beta-amino acids

Journal article

Secondary homochiral lithium amides derived from α-methylbenzylamine undergo highly diastereoselective conjugate additions to a range of α,β-unsaturated esters. The corresponding β-amino acids are readily liberated by successive N-debenzylation and ester hydrolysis, furnishing (R)-β-amino butyric acid, (R)-β-amino pentanoic acid, (S)-β-leucine, (R)-β-amino octanoic acid, (S)-β-phenylalanine, (S)-β-tyrosine methyl ether, (S)-β-tyrosine hydrochloride and (S)-β-(2-methoxyphenyl)-β-amino propanoic acid in high yields and high ee. The application of this procedure to the synthesis of the natural products (R)-β-DOPA and (R)-β-lysine is demonstrated. The development of a simplified one-pot reaction protocol applicable to the multi-gram scale synthesis of homochiral β-amino esters is also delineated. © 2006 Elsevier Ltd. All rights reserved.

Authors: Davies, S; Garrido, N; Kruchinin, D; Ichihara, O; Kotchie, L

• Publication status: Published
• Journal: TETRAHEDRON-ASYMMETRY
• Volume: 17
• Issue: 12
• Pages: 1793-1811
• Publication date: 2006-07-31
• DOI: 10.1016/j.tetasy.2006.05.008
• EISSN: 1362-511X
• ISSN: 0957-4166
• Language: English