Formation of heterocyclic compounds from 1,3-diazabuta-1,3-diene derivatives

Abstract

N-Trimethylsilyl(diphenylmethylene)amine gives quantitatively various open-chain 1,3-diazabutadienes (V) by coupling with benzimidoyl chlorides. The 1,3-diazabutadienes react with isocyanates, diphenylketen, diketen (4-methyleneoxetan-2-one), and dimethyl acetylenedicarboxylate to give the 3,4-dihydro-1,3,5-triazin-2(1H)-ones (VI), the azetidinone (VIII), the dihydro-1,3-oxazinones (XII), and the pyrimidinone (XIV), respectively.