A mild and efficient synthesis of novel isoxazolyl-benzo[4,5]oxazolo[3,2-a]pyrazines

Abstract

Synthesis of novel 2(3-methylisoxazol-5-yl)-4,10a-diaryl-2,10a-dihydro-1H-benzo[4,5]oxazolo[3,2-a]pyrazines 5 were simply achieved by the reaction of 2,2’-(3-methylisoxaol-5-yl)azanediyl)bis(1-phenylethanones) 3 with o-aminophenol 4 in the presence of CAN catalyst in CH₃CN solvent by adopting a new synthetic protocol. The required intermediates 3 were prepared by the interaction of 5-amino-3-methylisoxazole 1 with phenacyl bromides 2 in ethanol in the presence of K₂CO₃. The structures of newly synthesized compounds 3a-j and 5a-j have been confirmed by IR, ¹H NMR, ¹³C NMR and EI-MS data and by microanalytical data.