Rhodium-catalyzed coupling of arenes and fluorinated α-diazo diketones: synthesis of chromones.

Rhodium(III)-catalyzed C–C coupling of heteroarenes and fluorinated α-diazo diketones has been realized for the facile synthesis of 3-arylchromones. The reaction proceeds via chelation-assisted C–H activation, carbene insertion, and uncatalyzed intramolecular nucleophilic aromatic substitution, with C–F cleavage being accommodated in the nucleophilic aromatic substitution step. Three classes of heteroarenes have been defined with decent functional group tolerance. [ABSTRACT FROM AUTHOR]