Studies on 5-Bromodehydroacetic Acid : Synthesis of 1,5-Dipheny1-3-(5-bromo-4-hydroxy-6-methyl- 2H-pyran-2-one-3-yl)-2-pyrazolines

Department of Chemistry, University of Roorkee, Roorkee 247 672

Manuscript received 2 August 1978, revised 23 February 1979, accepted 27 April 1979

5-Bromodehydroacetic acid(I), on condensation with aromatic aldehydes in the presence of piperidine gave chalcone type compounds(II). Reaction of II with phenyl­hydrazines in ethanol-acetic acid afforded 1,5-dipheny1-3-(5-bromo-4-hydroxy-6-methyl­-2H-pyran-2-one-3-yl)-2-pyrazolines(IIi).