A Concise Route to 2-Amino-3-aryl-3H-benzofurans and their Use as Precursors to 3-Aryl-3H-benzofuran-2-one and 1H-Benzofuro[2,3-b]pyridin-2-one Derivatives

Abstract

A concise approach to 2-amino-3-aryl-3H-benzofurans based on the Michael addition of NaCN onto in situ generated substituted o-quinone methides has been developed. Straightforward access to 3-aryl-3H-benzofuran-2-ones was achieved upon acidic hydrolysis whereas N-Boc-protected 2-amino-3-aryl-3H-benzofurans underwent smooth intramolecular cyclisation to give 1H-benzofuro[2,3-b]pyridin-2-one derivatives.

Key words

furans - Michael additions - quinones - cyclisations - heterocycles

References

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