Improved synthesis of chalcones and pyrazolines under ultrasonic irradiation

Abstract

Five 1,3-diarylprop-2-en-1-ones 3a-e are synthesized by Claisen-Schmidt condensation of aryl methyl ketones and 4-chlorobenzaldehyde to give pyrazolincs 5a-c by cyclization with phenylhydrazine in gl. acetic acid using ultrasonic irradiation in lesser time with higher yields. All the synthesized compounds arc characterized by elemental analyses and spectral data IR, PMR and are screened for their antimicrobial activities. Some of them have shown promising results against E. coli, S. aureus, C. albicans and A. niger.