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Kinetics and mechanism of nitration of aromatic compounds using trichloroisocyanuric acid (TCCA)/NaNO2, TCCA‐N,N‐dimethyl formamide (TCCA‐DMF)/NaNO2, and TCCA‐N,N‐dimethyl acetamide (TCCA‐DMA)/NaNO2 under acid‐free and Vilsmeier‐Haack conditions. Reactions followed second‐order kinetics with a first‐order dependence on [Phenol] and [Nitrating agent] ([TCCA], [(TCCA‐DMF)], or [(TCCA‐DMA)] >> [NaNO2]). Reaction rates accelerated with the introduction of electron‐donating groups and retarded with electron‐withdrawing groups, but did not fit well into the Hammett's theory of linear free energy relationship or its modified forms like Brown‐Okamoto or Yukawa‐Tsuno equations. Rate data were analyzed by Charton's multiple linear regression analysis. Isokinetic temperature (β) values, obtained from Exner's theory for different protocols, are 403.7 K (TCCA‐NaNO2), 365.8 K (TCCA‐DMF)/NaNO2, and 358 K (TCCA‐DMA)/NaNO2. These values are far above the experimental temperature range (303‐323 K), indicating that the enthalpy factors are probably more important in controlling the reaction.

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Nitration of aromatic Compounds is triggered by Vilsmeier-Haack reagent (DMF/POCl3) or (DMF/SOCl2) in the presence of KNO3 or NaNO2 under conventional and non-conventional conditions. The reactions af- forded corresponding Nitro derivatives in very good yield with high regioselectivity. The results obtained in non-conventional methods (Micro wave irradiation, Grinding, Sonication) are comparable with those ob- tained under conventional conditions, but the reaction times of former conditions are substantially shorter than that of the latter

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