Iridium-Catalyzed B-H/C-H Dehydrogenative Coupling to Enable Boron-Nitrogen-Embedded Polycyclic Aromatic Hydrocarbons

Boron-nitrogen-embedded polycyclic aromatic hydrocarbons (BN-PAHs) represent a promising class of functional materials with tunable optoelectronic properties for applications in organic semiconductors, bioactive molecules, and sensing devices. However, precise functionalization of BN-PAHs at boron centers remains challenging, which relies on prefunctionalized substrates with limited step economy. Herein, we report an iridium-catalyzed intra- and intermolecular B-H/C-H dehydrogenative coupling reaction between 2,1-borazaronaphthalenes and hydrocarbons. This atom-economical catalytic platform offers a versatile and efficient approach to diverse BN-PAHs. The synthetic utility of this transformation is demonstrated by its broad substrate scope and good functional group tolerance. Furthermore, the practical value of this methodology is highlighted by its application in downstream derivatizations and the synthesis of optoelectronic functional molecules. The kinetic isotope effect (KIE) experiments and density functional theory (DFT) calculations revealed that the oxidative addition of the arene C-H bond to the iridium complex is likely the rate-determining step in this catalytic protocol.