Substrate‐Affinitive P‐Type Azapolycyclic Photosensitizer for Chemoselective Nitrilization Under Mild Conditions

ABSTRACT Herein we report azapolycyclic quinoxalinoquinoxaline (QQ) photosensitizers featuring both tunable reducing ability and hydrogen‐bonding assisted substrate affinity. The QQ‐Ar photosensitizers are easily accessible on the gram scale and can be purified via vacuum sublimation, highlighting their potential for vapor‐phase deposition in semiconductor applications. Their strong excited‐state reduction potentials ( E ( PC ^•+ / PC ^* ) = −1.76 to −2.05 V vs SCE) arise from tunable ground‐state oxidation potentials modulated by the aryl substituent. Despite the high reducing ability, the formation of honeycomb hydrogen‐bonding network with carbonyl substates enables direct nitrilization of primary amides under mild conditions. A broad range of aryl, heteroaryl, olefinic, and alkyl amides, as well as pharmaceutical derivatives, were converted to nitriles with high functional group tolerance and scalability. Spectroscopic and computational studies support a mechanism involving oxidative quenching and selective hydrogen atom abstraction. This work establishes QQ photosensitizers as a practical and versatile platform for amide‐to‐nitrile conversions under mild conditions, with potential utility in both industrial and synthetic applications.