Green approach using water mediated Diels-Alder reaction for the synthesis of some 2-(4-bromo-1-naphthyl)-3-(aryl)bicyclo[2.2.1]hept-5-ene methanones and evaluation of their antimicrobial and antioxidant activities

Abstract

Some (4-bromo-1-naphthyl)-(3-(substituted phenyl) bicyclo[2.2.1]hept-5-en-2-yl) methyl ketones were synthesized by fly-ash catalyzed environmentally benign Diels-Alder [4+2] cycloaddition reaction of 4-bromo-1-naphthyl chalcones and cyclopentadiene in water medium. In this reaction, the obtained yield was more than 60%. The synthesized methanones were characterized by their physical constants, microanalysis, infrared, nuclear magnetic resonance and mass spectroscopic data. The antibacterial and antifungal activities of these ketones were evaluated by the disc diffusion-zone of inhibition and two-fold serial-dilution-minimum inhibitory concentration of their corresponding bacterial and fungal strains using the Bauer-Kirby method. The antioxidant activities of these methanones were measured using the diphenyl picryl hydrazyl (DPPH) radical scavenging activity method.

Keywords

• diels-alder reaction, 4-bromo-1-naphtyl bicyclo[2.2.1]methanones, antimicrobial activities, antioxidant activity