Expedient asymmetric synthesis of all four isomers of N,N'-protected 2,3-diaminobutanoic acid

A J Robinson; P Stanislawski; D Mulholland; L He; H Y Li

doi:10.1021/jo001152f

Expedient asymmetric synthesis of all four isomers of N,N'-protected 2,3-diaminobutanoic acid

J Org Chem. 2001 Jun 15;66(12):4148-52. doi: 10.1021/jo001152f.

Authors

A J Robinson¹, P Stanislawski, D Mulholland, L He, H Y Li

Affiliation

¹ DuPont Pharmaceuticals Company, Chemical Process R&D, Experimental Station, Wilmington, Delaware 19880-0336, USA. A.Robinson@sci.monash.edu.au

PMID: 11397146
DOI: 10.1021/jo001152f

Abstract

2,3-Diaminobutanoic acid (DAB) is found in several peptide antibiotics, toxins, and biologically active molecules. This paper describes the practical and highly enantioselective synthesis of all four N,N'-protected DAB stereoisomers using an asymmetric Rh(I)-phosphine-catalyzed hydrogenation of isomeric enamides as the key step. Thermal and photochemical isomerization of the enamide hydrogenation substrates coupled with catalyst-geometric isomer pairing allows targeted synthesis of single DAB isomers in maximum yield.