Enantioselective synthesis of alpha-amino acids from N-tosyloxy beta-lactams derived from beta-keto esters |
| |
Authors: | Durham Timothy B Miller Marvin J |
| |
Affiliation: | Department of Chemistry and Biochemistry, 251 Nieuwland Science Hall, University of Notre Dame, Notre Dame, Indiana 46556-5670, USA. |
| |
Abstract: | A novel synthetic sequence has been developed to convert simple beta-keto esters into enantiomerically enriched alpha-amino acids. The key features of this sequence include the addition of azide to the C3 position of beta-keto ester derived N-tosyloxy-beta-lactams through a concomitant nucleophilic addition/N-O bond reduction reaction, a mild CsF-induced N1 benzylation of alpha-azido monocyclic beta-lactams, the preparation of alpha-keto-beta-lactams through a novel four-step sequence from the corresponding 3-azido-1-benzyl-beta-lactams, and TEMPO-mediated ring expansion of these compounds to the corresponding N-carboxy anhydrides (NCAs). In addition, the synthesis, isolation, and characterization of unusual 3-imino and 3-chloramino-beta-lactams is reported. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|