Synthesis of 1-H-3-(Substituted Phenyl)-5-(Substituted Phenyl)-2-Pyrazoles and Their Derivatives

P. J. Parmar¹*, S. I. Rajput² and A. G. Doshi¹

¹Department of Chemistry, Vidyabharti Mahavidyalaya, Amravati - 444 602 (India) ^{2Department of Chemistry, B.P. Arts, S.M.A. Science and K.K.C. Commerce College, Chalisgaon - 424 101 (India)} 

Chalcones(III a-d) were suspended in glacial acetic acid and bromine in acetic acid reagent (25% w/v) to give chalcone disbromides (IVa-c). Chalcones (IIIa-d) or flavones (Va-d) were treated with hydrazine hydrate, aqueous KOH in ethanol to give same pyrazoles (VIa-c) from both methods. Pyrazoles (VIa-d) was reacted with acetic acid to form 1-acetyl pyrazoles (VIIa-d). Pyrazoles (VIa-d) or 1-acetly pyrazoles (VIIa-d) was reacted with acetic anhydride and a pinch of anhydrous sodium acetate to give 1-acetly-3-(2-acetoxy) pyrazoles (VIIe-h) from both methods. Pyrazoles (VIa-d) were condensed with benzoyl chloride in pyridine medium to give 1-benzoyl pyrazoles (VIIi-l).

Synthesis; flavones; pyrazoles derivatives of pyrazoles