R. Wagner, J. Tilley
Dec 1, 1990
Citations
0
Influential Citations
22
Citations
Journal
Journal of Organic Chemistry
Abstract
(2S,3S)-N-Boc-3-(benzyloxy)aspartic acid β-benzyl ester (2), a β-hydroxyaspartic acid derivative suitably protected for incorporation into peptides by solid-phase synthesis, was synthesized from N-Boc-(R)-serine via the intermediate. [4R-(R*,R*)]-4-[hydroxy[2-(trimethylsilyl)ethynyl]methyl]-2,2,-dimethyl-3-oxazolidinecarboxylic acid 1,1-dimethylethyl ester (5). Key transformations involved the ruthenium tetraoxide mediated oxidation of the ethynyl moiety to form the β-carboxylic acid and, after esterification and oxazolidine ring hydrolysis, dichromate oxidation of the resulting primary alcohol to the α-carboxylic acid. The method is suitable for the preparation of gram quantities of 2