Regioselective One-pot transformation of ۲’-hydroxy chalcones to ۳,۵-diphenylisoxazole via dehydrogenation of dihydroisoxazolines using Copper salt in DMF

A synthesis of series of ۳, ۵-diaryl isoxazoles has been described. The Cu salt in DMF with EDU base induces oxidative dehydrogenation of ۲-(۵-phenyl-۴,۵-dihydroisoxazol-۳-yl) phenol results in the formation of ۲-(۵-phenylisoxazol-۳-yl) phenol in excellent yields under mild reaction conditions. The present protocol contains cheap catalyst, easy workup, normal reaction conditions and high selectivity.

Keywords:

dehydrogenation , Cu salt , ۲’ -hydroxy chalcones , ۳ , ۵-diphenylisoxazole , dihydroisoxazolines