Redox-Neutral Iron–Sulfur Promoted Transformation of 2-Nitrophenols and 2,6-Disubstituted p-Cresols into 2-Arylbenzoxazoles

Abstract

A catalyst based on iron and elemental sulfur has been shown to efficiently promote a redox-neutral reaction between 2-nitrophenols and 2,6-disubstituted p-cresols, allowing for the preparation of 2-arylbenzoxazoles in good yields. This synthetic methodology also affords high atom economy without the use of any external oxidizing and/or reducing reagents. This is the first redox–condensation reaction of 2-nitrophenols with 2,6-disubstituted p-cresols.

Key words

heterocycles - iron - sulfur - annulation - domino reaction

• References and Notes

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