Visible-Light Mediated Radical Alkylation of Flavones: A Modular Access to Nonsymmetrical 3,3″-Biflavones
Daniela Fregoso-López1, Luis D Miranda1
1Instituto de Química, Universidad Nacional Autónoma de México, Ciudad de México 04510, México.
Abstract:
The first synthetic strategy for nonsymmetrical 3,3″-biflavones is described. To this end, a novel visible-light iridium-catalyzed radical C-3 alkylation of flavones with o-methoxy phenacyl bromides was developed. Selective demethylation of the alkylated flavones and acylation through a Baker-Venkataraman rearrangement with diverse acyl chlorides afforded a library of 20 structurally novel biflavones. This modular strategy rapidly expands the structural complexity and diversity of these privileged scaffolds.
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