Synthesis of fully arylated (hetero) arenes by coupling reaction

Multiply arylated (hetero) arenes are intriguing structural motifs in functional molecules, such as natural products, pharmaceuticals and functional organic materials. In recent decades, many synthesis methods of multiply arylated (hetero) arenes have been reported. As a subclass of multiply arylated arenes, fully arylated (hetero) arenes have also flourished as a unique structural class in functional organic materials and biologically active compounds. Despite the successful application of fully arylated (hetero) arenes with different aryl substituents, the synthesis of such (hetero) arenes has not been explored compared to partially arylated arenes due to the difficulty of synthesizing sterically hindered and highly unsymmetrical aromatic cores. This review reports the synthesis of fully arylated (hetero) arenes bearing more than two different aryl substituents and categorizes this emerging topic by the type of (hetero) arene core, focusing on the methods employing cross-coupling reaction including direct C-H arylation.