Synthesis of 1-H-3-(2''-Hydroxy-3''-substituted-5''-Chlorophenyl)-5-(2'-Furyl)-2-Pyrazoles and Their Derivatives

Abstract

2-Hydroxy-3-substituted - 5-chlorophenyl - β-(2'-furyl)-acrylophenone dibrrllnide
(Ia-c) reacts with hydrazine hydrate in ethanol and yields pyrazole
(IIa-c). Similarly, β-(2'-furyl)-acrylophenone dibromide (Ia-c) reacts with
phenylhydrazine hydrochloride in ethanol medium and gives 1-phenylpyrazole
(IIIa-c). Pyrazole (IIa-c) reacts with acetic acid to form 1-acetyl
pyrazole (IVa-c). Also pyrazole (IIa-c) on reaction with benzoylchloride
in pyridine gives 1-benzoylpyrazole (Va-c). Characterisation and structural
elucidation were done on the basis of chemical reactions, elemental
analysis and spectral data.