Modular Approach to Silicon-Bridged Biaryls: Palladium-Catalyzed Intramolecular Coupling of 2-(Arylsilyl)aryl Triflates

Copper-catalyzed direct C arylation of heterocycles with aryl bromides: discovery of fluorescent core frameworks

A window of opportunity: A general copper-catalyzed C-H bond-activation path allows arylation of heterocycles with a wide range of aryl bromides (see scheme). The reaction shows excellent regioselectivity and exhibits good functional group tolerance. The 8-aryl xanthines exhibit fluorescence in a variety of solvents and show promise as reagents for biological imaging.

Fluorescent diarylindoles by palladium-catalyzed direct and decarboxylative arylations of carboxyindoles

Simple and brilliant: 1-Substituted 1H-indole-2-carboxylic acids efficiently undergo successive diarylation accompanied by C-H bond cleavage and decarboxylation upon treatment with aryl bromides in the presence of a palladium catalyst system to afford fluorescent 2,3-diarylindoles. This facile synthetic method provides a highly efficient blue emitter with a quantum yield of 0.97 in the solid state (see scheme).