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N‐Bromophthalimide (NBP)‐triggered bromination of aromatic compounds has been studied in the presence of aqueous acetic acid. Reaction Kinetics indicated first order in [NBP] and zero order in [Anisole]. The reactions afforded very good yields of corresponding bromo derivatives under kinetic conditions. The mechanism of the reaction is explained through the formation of acetyl hypobromite due to the interaction of NBP and acetic acid, which in turn reacts with anisole to afford a bromo derivative of anisole.

Synthesis and kinetics of potassium periodate(KIO4)/NaNO2/KHSO4)‐initiated nitration of aromatic compounds have been studied in aqueous acetonitrile medium. Synthesis of nitroaromatic compounds is achieved under conventional and solvent‐free microwave conditions. Reaction times in microwave‐assisted reaction are comparatively less than in conventional reaction. The reaction kinetics for the nitration of phenols in aqueous bisulfate and acetonitrile medium indicated first‐order dependence on [phenol], [NaNO2], and [KIO4]. An increase in [KHSO4] accelerated the rate of nitration under otherwise similar conditions. The rate of nitration increased in the solvent of high dielectric media (solvents with high dielectric constant (D)). Observed results were in accordance with Amis and Kirkwood plots [log k′ vs. (1/D) and [(D − 1)/(2D + 1)]. These observations probably indicate the participation of anionic species and molecular or (dipolar) species in the rate‐determining step. In addition, the plots of (log k′) versus volume% of organic solvent were also linear, which probably indicate the importance of both electrostatic and nonelectrostatic forces, solvent–solute interactions during nitration of phenols. Reaction rates accelerated with the introduction of electron‐donating groups and retarded with electron‐withdrawing groups, but results could not be quantitatively correlated with Hammett's equation and depicted deviations from linearity. These deviations could probably be attributed to cumulative effects arising inductive, resonance, and steric effects. Leffler's plot (ΔH# vs. ΔS#) was found linear indicating the compensation (cumulative) effect of both enthalpy and entropy parameters in controlling the mechanism of nitration.

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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.

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