Synthesis of novel cyclic hydroxamic acids

Article abstract of DOI:10.1016/S0040-4039(00)73101-7

The nitroacetyl (S)-proline esters (1,3,5) are reduced by zinc-NH₄Cl to the hydroxylamine stage and cyclized to provide the novel chiral bicyclic hydroxamic acids (2,4,6). Michael addition of allyl acrylate on nitroacetic acid derivatives followed by Pd(0) catalyzed intramolecular allyl transfer and subsequent reduction of the nitro group yielded a novel class of cyclic hydroxamic acids related to pyroglutamic acid.