Rapid synthesis and interconversions of fatty 4,5-dihydroimidazoles and fatty 1,4,5,6-tetrahydropyrimidines. Thermal cyclizations of fatty amides involving phenyl phosphorodiamidate

Abstract

Brief heating of ethane-1,2- and propane-1,3-bis-fatty amides at 235–250 °C with phenyl phosphorodiamidate gave routes to high yields of 2-fatty alkyl-4,5-dihydroimidazoles and 1,4,5,6-tetrahydropyrimidines. Ready interconversions of fatty dihydroimidazoles and tetrahydropyrimidines, involving diamine exchange with solvent, were observed on brief heating of these materials in ethylenediamine and trimethylenediamine as solvents.