Solvent-free synthesis, spectral correlations and antimicrobial activities of some 3,4-dimethoxy chalcones

Background: The aim of this study was to synthesise some substituted styryl 3,4-dimethoxy phenyl ketones using solvent-free SiO2–H2SO4 catalyzed aldol condensation between 3,4-dimethoxy acetophenone and substituted benzaldehydes under microwave irradiation. Then to characterize them by their analytical, physical and spectroscopic data, and also to study their the spectral correlation and antimicrobial activities. Methods: Solvent free microwave assisted aldol condensation method was used for synthesising 3,4-dimethoxyphenyl chalcones. They were characterised by ultraviolet (UV), infrared (IR), nuclear magnetic resonance (NMR) and mass spectroscopic data. The UV, IR, NMR spectral data were correlated with substituent constants, F and R parameters, using Hammett equation, to study the effect of substituents. The Bauer-Kirby method was used for evaluation of antimicrobial activities of the synthesised chalcones. Results: Yields of synthesised chalcones were more than 85%. The spectral data of these ketones h...