Kinetics and reactivity of substituted anilines with 2‐chloro‐5‐nitropyridine in dimethyl sulfoxide and dimethyl formamide

The kinetics of the reaction of substituted anilines with 2‐chloro‐5‐nitropyridine were studied in dimethyl sulfonide (DMSO) and dimethyl formamide (DMF) at different amine concentrations and temperatures in the range 45–60°C. In both solvents the reaction was not a base‐catalyzed one. A plot of ΔH# versus ΔS# for the reaction in DMSO and DMF gave good straight lines with isokinetic temperatures 128°C and 105°C, respectively. Good linear relationships were obtained from the plots of log k1 against σ° values at all temperatures with negative ρ values (−1.63 to −1.28 in DMSO) and (−1.26 to −0.90 in DMF).