Synthesis of 2,3-Disubstituted Benzofurans from ortho-Acylphenols

Abstract

2,3-Disubstituted benzofuran derivatives were synthesized from ortho-acylphenols in two steps. The β-aryloxyacrylates prepared from the ortho-acylphenols were treated with n-Bu₃SnH/AIBN and then with 5% HCl-EtOH to afford 2,3-disubstituted benzofurans.

Key words

benzofurans - cyclizations - dehydrations - phenols - radical reactions

References

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  Other substrates were prepared from salicyl aldehyde and ortho-vanillin in two steps [1) RMgBr, THF; 2) MnO₂, benzene].