The facile and efficient ultrasound-assisted synthesis of new quinoline-appended ferrocenyl chalcones and their properties

The facile and efficient synthesis of quinoline-appended ferrocenyl chalcones via the condensation of acetylferrocene (or substituted 2-methyl-3-acetylquinoline) with 2-chloro-3-formylquinoline (or ferrocenecarboxaldehyde) in ethanol under basic conditions by the ultrasonic method is reported and compared to the results of synthesis achieved through conventional methods. Two derivatives were investigated crystallographically which confirmed the E-conformation about the CC ethylene bond in each case. Redox chemistry of the new chalcones was investigated by cyclic voltammetry which showed quasi-reversible one-electron redox processed with potentials correlated with electron-withdrawing substituents. The compounds showed promising antimicrobial properties, with derivatives 3a and 6a showing the maximum activity against bacterial and fungal strains, respectively.

Graphical abstractThe synthesis of ferrocene and quinoline-appended chalcones in high yield and purity by an ultrasound-assisted method is reported along with their spectral, electrochemical and biological properties. The predominance of the E-conformation of the CC bond in chalcones has been established via1H NMR and X-ray crystallography.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Efficient ultrasound assisted synthesis of novel chalcones. ► Synthesis of ferrocene and quinoline appended chalcones in high yield and purity. ► Spectral, electrochemical and biological properties of chalcones.