IT has been claimed1,2 that the reaction of s-trinitrobenzene with certain amines involves a proton transfer mechanism. Evidence given in support of this claim was not very satisfactory, and in fact it has been clearly shown by exchange measurements3,4 on similar systems that no proton transfers occur. Other evidence is either conflicting, as is the case with certain electrolysis measurements5,6, or irrelevant, having been obtained under very different experimental conditions7.