Eight dienic nitrogen compounds were prepared starting from cyclobutene lactam 8. Dienes 12-15 were obtained by benzylation or acylation followed by methanolysis, hydrolysis or reduction. The unsubstituted lactam 8 provided diene 16. The latter was a precursor for the mono and biacylated products 17-19.
The reactions of sec-aminodienylesters 2, which were prepared by the reactions of methyl 5-(N, N-dimethylamino)-2, 4-pentadienoate (tert-aminodienylester 1) with primary amines, with acetaldehyde afforded 2, 3-dihydro-6H-1, 3-oxazines 3, providing a new heterocyclic annelation reaction.