An Annulative Synthetic Strategy for Building Triphenylene Frameworks by Multiple C-H Bond Activations

C-H activation is a versatile tool for appending aryl groups to aromatic systems. However, heavy demands on multiple catalytic cycle operations and site-selectivity have limited its use for graphene segment synthesis. A Pd-catalyzed one-step synthesis of functionalized triphenylene frameworks is disclosed, which proceeds by 2- or 4-fold C-H arylation of unactivated benzene derivatives. A Pd-2(dibenzylideneacetone)(3) catalytic system, using cyclic diaryliodonium salts as pi-extending agents, leads to site-selective inter-and intramolecular tandem arylation sequences. Moreover, N-substituted triphenylenes are applied to a field-effect transistor sensor for rapid, sensitive, and reversible alcohol vapor detection.