K. Laue, Christian Mück‐Lichtenfeld, G. Haufe
Aug 20, 1999
Citations
0
Influential Citations
27
Citations
Journal
Tetrahedron
Abstract
Abstract Diastereoselective alkylation of ( R )-(+)-camphor-based glycine or alanine esterimines with 3-bromo-2-fluoropropene after hydrolytic deprotection gave ( R )-(+)-2-amino-4-fluoropent-4-enoic acid with 38% overall yield and 90% ee, or ( R )-(+)-2-amino-4-fluoro-2-methylpent-4-enoic acid (19% overall yield, 59% ee), respectively. Deprotection under drastic conditions was accompanied by hydrolysis of the fluorovinyl moiety to give ( R )-(−)-2-amino-4-oxopentanoic acid hydrochloride with 28% overall yield and >95% ee. Ab initio calculations of acetamide and 2-fluoropropene as models for a primary amide or a fluorovinyl group despite of their different electronic structure show a similar electrostatic potential on the van der Waals surface suggesting their isosteric behavior.