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A new mode of carbene‐catalyzed heteroatom activation and asymmetric reactions is disclosed. The reaction starts with addition of a carbene catalyst to a (benz)imidazole‐derived aldimine substrate. Subsequent oxidation and proton transfer lead to the formation of a catalyst‐bound triaza‐diene as the key intermediate, in which the nitrogen atom at a site remote to the catalyst‐substrate bond is activated. This unusual triaza‐diene intermediate then undergoes highly enantioselective reactions with activated ketones through a concerted asynchronous pathway, as supported by mechanistic studies and preliminary density function theory calculation. [ABSTRACT FROM AUTHOR]