Substituent effect in the reaction of aryl arylmercury sulphides with picryl iodide
Abstract
The rates of the reaction of a series of substituted aryl arylmercury sulphides (Ar1HgSAr2) with picryl iodide in benzene at 30° have been measured. Electron-donating substituents located in Ar1 and in Ar2 enhance the reaction rate whereas electron-withdrawing substituents have the opposite effect. The logarithmic plots of rate against σ constants give ρ values of –0.966 (substituents in Ar1) and –3.67 (substituents in Ar2). o-Methyl groups in Ar1 have little steric effect whereas o-methyl groups in Ar2 strongly depress the reaction rate.