The kinetics of the coupling of N1-methyl-4-nitro-2,1,3 benzothiadiazolium tetrafluoroborate 1 with a series of 4-X-substituted anilines 2a-f (X = OH, OMe, Me, H, Cl, and CN) have been investigated in acetonitrile at 20°C. The second-order rate constants result in a