Preparation of cyclic and bicyclic beta-amino acids derivatives from methyl 6-ethoxy-5,6-dihydro-4H-1,2-oxazine-4-carboxylate

摘要

The readily available methyl 6-ethoxy-5,6-dihydro-4H-1,2-oxazine-4-carboxylate (1) was alkylated at C-4 and acylated at the nitrogen atom. 1,2-Oxazine 1 and the resulting new substituted 1,2-oxazines 2 and 3 were suitable precursors for the preparation of derivatives of beta-proline, nipecotic acid, as well as indolizine-6- and quinolizine-3-carboxylic acids. [References: 24]