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A direct annulation reaction of N-benzimidazolyl amidines with aldehydes has been established and allows the synthesis of ortho-fused 1,3,5-triazine derivatives. The N-benzimidazolyl amidine substrates are readily accessible by the addition of 2-aminobenzimidazoles to the corresponding nitriles. In the presence of molecular iodine and copper iodide, cyclization of benzimidazolyl amidines with various aldehydes in toluene under reflux followed by oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) gives the corresponding products. In this reaction, iodine acts more as a Lewis acid catalyst than as an oxidant. This synthetic process is insensitive to air and operationally simple, and provides facile access to a variety of novel 1,3,5-triazino[1,2- a]benzimidazoles and related heterocycles. [ABSTRACT FROM AUTHOR]