Abstract Light-induced cyclization of several substituted 2-(2-fluorophenylazo) azines in the presence of Ca 2+ ions to the corresponding triazinium derivatives is investigated experimentally and computationally. The azo derivatives of 4-methylpyridine 4 undergo facile cyclization to the corresponding triazinium 1, and the rate of cyclization increases with increasing number of fluorine atoms at the benzene ring. No triazinium ions were obtained ...
