Bi(OTf)3-Mediated (4+1) Annulation of α-Sulfonyl o-Hydroxyacetophenones with α-Hydroxy Arylketones to Access Sulfonyl 2-Aroylbenzofurans

In this paper, a high-yield, facile route for the scalable synthesis of sulfonyl 2-aroylbenzofurans via a Bi(OTf)(3)-mediated intermolecular double cyclocondensation of alpha-sulfonyl o-hydroxyacetophenones with substituted alpha-hydroxy arylketones under mild open-vessel reaction conditions is described. In the overall reaction, water is generated as the only byproduct. Various metal triflate-promoted reactions and conditions are investigated for the efficient one-pot (4 + 1) annulation reaction.

Automated summary

This paper presents a high-yield and facile method for the synthesis of sulfonyl 2-aroylbenzofurans under mild conditions with water as the only byproduct. Various metal triflate-promoted reactions were investigated for efficient annulation reaction.