In the present study, N-methyl-2,4,6-cycloheptatriene-1-imine (troponimine) with (Me)2N- and MeOsubstituents has been investigated theoretically to evaluate its suitability as a new neutral organic superbase. To introduce the aforementioned system, thermochemical parameters such as gas basicity and proton affinity have been calculated along with pKBH+ values in acetonitrile. The results revealed that all of the studied troponimine derivatives were more basic than 1,8-bis(dimethylamino)-naphthalene whose gas phase basicity of 237 kcal mol-1 is considered to be the borderline between ordinary bases and superbases. However, the most important finding was that some of the proposed troponimines were much stronger bases than the well-established cyclopropenimine superbases. The origin of troponimine basicity was elucidated through NICS calculations which revealed that the troponimines become aromatic upon protonation. AIM analyses revealed that a hydrogen bond could also contribute to the basicity if a suitable substituent is located adjacent to the imine group of the troponimine.

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