Synthesis, Characterization, and Biological Activity of Chromium Complexes as Efficient and Novel Catalysts for Direct Synthesis of Carbonyl Compounds from Benzyl/Cycloalkyl Bromides in Water under Aerobic Oxidation

The oxidation process of benzylic halides especially benzylic bromide to corresponding carbonyl compounds such as aldehydes and ketones is a worthwhile and important organic reaction in industrial and laboratory synthetic organic chemistry. In the present study, an efficient and novel method to obtain carbonyl compounds using benzyl bromide with a catalytic amount of chromium complexes in water under aerobic conditions was reported. The six types of chromium complexes were prepared via the reaction mixture of four ligands. The prepared ligands and chromium complexes were characterized using Fourier transform spectroscopy (FT-IR), elemental analysis, molar conductivity, and magnetic moment, as well as UV-Vis spectroscopy. Different benzyl bromide derivatives were selected with both electron-donating groups and electron-withdrawing groups at –ortho, -meta, and –para positions. Under the optimum conditions, the corresponding benzaldehyde derivatives were obtained in moderate to excellent yields. In addition, the biological activity of the prepared chromium complexes was checked.