Synthesis of heterocyclic compounds using amidines as their ene-1,1-diamine tautomers, iv: Synthesis of n-bridged heterocycles 1,2,3,4-tetrahydropyrido[1, 2-a]pyrimidin-6-ones and methyl 1,2,3,4-tetrahydropyrrolo- [1,2-a]pyrimidin-7- ylideneacetates

Article abstract of DOI:10.1080/00397911.2010.517365

2-Benzyl-1,4,5,6-tetrahydropyrimidines 1 (as ene-1,1-diamine N,C-tautomers) in diglyme reacted with ethyl benzoylacetate at 160 °C in an oil bath to give 1,2,3,4-tetrahydropyrido[ 1,2-a]pyrimidin-6-ones 3 and with dimethyl acetylenedicarboxylate in methanol at room temperature, leading to methyl 1,2,3,4-tetrahydropyrrolo[1,2-a]pyrimidin-7- ylideneacetates 5, respectively. Copyright Taylor & Francis Group, LLC.