Fast Synthesis of Heterobicycles Containing a Bridgehead Nitrogen Atom in Dry Media under Microwave Irradiation

Abstract

1,ω-Alkanediamines 1a-c or ω-aminoalcohols 5a-d adsorbed over alumina or montmorillonite K₁₀ react with ethyl levulinate [ethyl 4-oxopentanoate (2)] under microwave irradiation to give, within a few minutes, compounds such as 7a-methyl-2,3,7,7a-tetrahydro-1H-pyrrolo [1,2-a]imidazol-5(6H)-one (3a) and 7a-methyl-2,3,7,7a-tetrahydropyrrolo[2,1-b]oxazol-5(6H)-one (6a).