Enantioselective syntheses of (R)- and (S)-hexahydropyridazine-3-carboxylic acid derivatives

Article abstract of DOI:10.1055/s-1996-4192

Appropriately protected optically active tetrahydropyridazine-3-carboxylic acid and hexahydropyridazine-3-carboxylic acid were prepared via ring closure of α-hydrazino- and δ-hydrazinopentanoates. Either optically active glutamic acid or an enantioselective catalytic hydrogenation was used to generate the chiral center. The numerous optically active intermediates are valuable starting materials for the synthesis of other unusual amino acids.