Kinetics and mechanism of mercuriation of aromatic compounds by mercury trifluoroacetate in trifluoroacetic acid

Abstract

The mercuriation of a series of aromatic derivatives by mercury(II) trifluoroacetate in trifluoroacetic acid has been studied using titrimetric and spectrophotometric methods. The latter method has revealed the presence of a rapidly formed π-complex intermediate and values of the thermodynamic parameters of its formation have been computed. Only small kinetic isotope effects were found for the complex-forming step in contrast to the large values obtained for the slow step. The effect of added salts was investigated and the mechanism of the reaction discussed in detail in the light of these results. Mercuriation by a readily synthesised mixed acetate, Hg(OCOCF₃)(OCOCH₃), is also reported as well as some preliminary studies of triptycene derivatives.