Highly Efficient Method for Synthesis of Benzoquinones Using Hypervalent Iodine(III) Reagent and Sodium Bisulfate

Abstract

A rapid, one-step, novel approach for the conversion of benzamides into benzoquinones using (diacetoxyiodo)benzene(III) and sodium bisulfate has been developed in aqueous acetonitrile at room temperature. The developed protocol is applicable to several types of substituted benzamide derivatives to get the corresponding benzoquinone products. The developed methodology offers mild reaction condition, short reaction time, and moderate to excellent yields. This is one of the most simple and environmentally benign protocols for synthesis of benzamide derivatives.

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GRAPHICAL ABSTRACT

Keywords:

• Benzamides
• benzoquinones
• hypervalent iodine
• sodium bisulfate

ACKNOWLEDGMENT

K. A. S. is thankful to the Council of Scientific and Industrial Research (New Delhi) for the award of a Senior research fellowhip and financial support.

Notes

^a Reaction conditions: Benzamide (1 mmol) in water–acetonitrile (1:1) as solvent at room temperature.

^a Reaction conditions: amides (1 mmol), (diacetoxyiodo)benzene (5 mmol), sodium bisulfate (1 mmol) in aqueous acetonitrile (10 mL) at room temperature.

^b Products were characterized using ¹H NMR, IR, and mp/bp and compared with literature data.

^c Isolated yields of pure products.