Tandem Oxidation Process Using Ceric Ammonium Nitrate: Three-Component Synthesis of Trisubstituted Imidazoles Under Aerobic Oxidation Conditions

Abstract

By combining a ceric ammonium nitrate (CAN)–catalyzed aerobic oxidation of α-hydroxy ketones with a subsequent three-component condensation reaction using aldehydes and ammonium acetate, highly substituted imidazole derivatives can be assembled. This reaction is an important approach for the synthesis of highly substituted imidazole derivatives and was carried out in good to excellent yields in ethanol as an environmentally benign solvent.

Keywords:

• Aerobic oxidation
• ceric ammonium nitrate (CAN)
• tandem oxidation process (TOP)
• three-component reaction
• trisubstituted imidazole

ACKNOWLEDGMENT

We gratefully acknowledge the financial support from the Research Council of Shahid Beheshti University.

Notes

^a Benzoin (1 mmol), benzaldehyde (1 mmol), and ammonium acetate (6 mmol).

^b Isolated yields.

^c In the absence of the catalyst.

^d Without air blowing.

^a Isolated yields.