Fully Fused Hydrazine-Embedded Nanographene with Near-Infrared Chiroptical Emission

Embedding hydrazine into graphenic networks, where two graphitic nitrogen atoms are directly linked by an N–N bond, endows unique redox activity and antiaromatic character, yet the construction of such fully fused architectures has remained a synthetic challenge. Here we report the first fully fused hydrazine-embedded nanographene ( 1 ) synthesized via a dehydrocyclization strategy. Single-crystal X-ray diffraction revealed a hydrazine moiety embedded within a fused polycyclic carbon framework measuring 1.4 nm diagonally with a helical saddle-shape. This π-extended architecture displays near-infrared (NIR) absorption (830 nm) and emission (879 nm, Φ F = 6.5%), as well as multistep redox processes accompanied by oxidation-induced planarization and an antiaromatic-to-aromatic transition. Chiral resolution further uncovered circularly polarized luminescence extending beyond 850 nm, which is observed for the first time from a helical nanographene. This study demonstrates that hydrazine embedment can be exploited to construct atomically precise nanocarbons with distinctive redox and NIR optical functions.