A facile synthesis of 1,3-diphenyl-4-arylspiro[pyrazoline-5,3′-flavan-4′-one] †

Abstract

Synthesis of a series of novel 1,3-diphenyl-4-arylspiro[pyrazoline–5,3′-flavan-4′-ones] has been accomplished in good yields by the regioselective 1,3-dipolar cycloaddition of diphenylnitrilimine with (E) 3-benzylideneflavan-4-ones.