Efficient Synthesis of Some New 2,3-Dimethylquinoxaline-1-oxides Using Bis(acetoxy)phenyl-λ³-iodane as an Oxidant

Abstract

A series of 2-(arylimino)-3-(hydroxyimino)butanes 3a–g, easily accessed by the condensation of variously substituted anilines 1a–g with biacetyl monoxime 2, were efficiently cyclized to afford 2,3-dimethylquinoxaline-1-oxides 4a–g using bis(acetoxy)phenyl-λ ³-iodane as an oxidant. This methodology utilizes a commercially available and environmental benign oxidant to achieve the title compounds in excellent yields under mild conditions.

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GRAPHICAL ABSTRACT

Keywords:

• 2-(Arylimino)-3-(hydroxyimino)butanes
• bis(acetoxy)phenyl-λ ³-iodane
• 2,3-dimethylquinoxaline-1-oxides

ACKNOWLEDGMENTS

The authors are grateful to the Council of Scientific and Industrial Research, New Delhi, India, for providing financial assistance to Chinu Rani, in the form of junior and senior research fellowships. Thanks are also extended to the Sophisticated Analytical Instrument Facility, Central Drug Research Institute, Lucknow, for providing elemental analyses.