title: Enaminones in heterocyclic synthesis: a novel route to tetrahydropyrimidines, dihydropyridines, triacylbenzenes and naphthofurans under microwave irradiation.
abstract: Condensation of phthalimidoacetone (1) with DMFDMA (N,N-Dimethylformamide dimethyl acetal) has afforded enaminone 2. Refluxing 2 with equimolecular amounts of benzaldehyde and urea in acetic acid afforded a mixture of tetrahydropyrimidine 5 and the dihydropyridine 6. Compound 2 undergoes self-condensation on heating in acetic acid or under microwave irradiation in presence of acidic zeolite to give 1,3,5-triacylbenzene 9. Reacting enaminone 11a with naphthoquinone 15 afforded the naphthofuran 18. The possible formation of the aldehyde 19 was excluded based on an HMQC experiment, which revealed that the carbonyl carbon is not linked to any hydrogen.
authors.affiliation: Department of Chemistry, Faculty of Science; Kuwait University, P.O. Box 5969 Safat 13060, Kuwait. saleh.almousawi@yahoo.com
authors.forename: Saleh Mohammed
authors.initials: SM
authors.lastname: Al-Mousawi
authors.forename: Morsy Ahmed
authors.initials: MA
authors.lastname: El-Apasery
authors.forename: Mohamed H
authors.initials: MH
authors.lastname: Elnagdi
mesh_terms: D001554:Benzene / Q000138:chemical synthesis* / Q000737:chemistry; D004095:Dihydropyridines / Q000138:chemical synthesis* / Q000737:chemistry; D005663:Furans / Q000138:chemical synthesis* / Q000737:chemistry; D006574:Heterocyclic Compounds, 2-Ring / Q000138:chemical synthesis* / Q000737:chemistry; D008872:Microwaves; D011743:Pyrimidines / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D004095:Dihydropyridines; D005663:Furans; D006574:Heterocyclic Compounds, 2-Ring; D011743:Pyrimidines; D001554:Benzene