Hydroxyapatite catalyzed cyclization of aryl enones: Solvent-free efficient synthesis of some 4-aryl-5,6-dihydro- 6-(substituted phenyl)-4H-1,3-oxazine-2-amines

Some 4-aryl-5,6-dihydro-6-(substituted phenyl)-4H-1,3-oxazine- 2-amine derivatives including 4-(4-methyl-1-naphthyl)-5,6- dihydro-6-(substituted phenyl)-4H-1,3-oxazine-2-amines have been synthesised by hydroxyapatite catalyzed solvent-free cyclization of aryl chalcones and urea using microwave irradiation under solventfree condition. The yields of the oxazines were more than 85%. The synthesised oxazine amines have been characterized by their physical constants, analytical and spectroscopic data.