A series of partially fused N‐doped nanographenes (2–4) are synthesized via the oxidative cyclodehydrogenation of oligoaryl‐substituted dibenzo[e,l]pyrene (1), and five, six, and seven new C−C bonds are formed, respectively, implying stepwise C−C bond fusion and extended π‐conjugation. Single‐crystal X‐ray diffraction analysis of compound 4 a revealed that the presence of sterically demanding groups hindered the formation of planar and fully fused nanographene in the oxidative cyclodehydrogenation reaction step. Optical study of compounds 2 to 4 showed that extended π‐conjugation leads to a regular stepwise bathochromic shift in the absorption and emission spectra. Furthermore, the HOMO–LUMO gaps of these compounds exhibit a decrease as C−C bond formation proceeds. Thus, the optoelectronic properties of nanographenes are highly dependent on the formation of new C−C bonds in the molecular skeleton.

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