Rh(III)‐Catalyzed Perimidine Directed C−H Activation/Annulation for the Synthesis of Hexacyclic Cationic Azaperylenes

Annulative π‐extension for the synthesis of cationic azapyrenes has been widely researched, while access to larger π‐systems such as azaperylenes is rare. Herein, perimidine is reported as a fresh directing group to trigger Rh(III)‐catalyzed dual C−H activation/annulation of 2‐aryl perimidines and alkynes, constructing hexacyclic perimidinium salts (benzo‐azaperylenes) A . Salts A could also be synthesized via three‐component triple C−H annulation from commercial naphthalene‐1,8‐diamine, aldehydes, and alkynes. A hexacyclic BF 2 complex B1 is conveniently prepared from HO‐substituted perimidine. Three rhodacycles have been detected by ESI‐MS to support the proposed mechanism. The photophysical properties, such as absorptions, emissions, and cyclic voltammetry of these novel cations, are characterized. Salts A show tunable luminescence (516–602 nm) affected by the group from perimidine more than alkyne, and BF 2 complex B1 shows emission peaking at 602 nm. The counteranions also have influence on the luminescence, with an order of Cl > BF 4 > OTf > SbF 6 .