The stabilities of Meisenheimer complexes. Part 24. Some reactions of 2,4,6-trinitrotoluene and 2,4,6-trinitrobenzyl chloride with bases

Abstract

Kinetic and spectroscopic studies of the reaction of 2,4,6-trinitrobenzyl chloride (TNBCI) with alkoxides allow the identification of three processes resulting from 1 : 1 interaction. These are σ-complex formation by base addition at the 3- or 1-positions and transfer of a side-chain proton. In contrast with the behaviour of 2,4,6-trinitrotoluene the more stable σ-adduct derived from TNBCI results from addition at the 1-position and has a stability comparable with that of the conjugate base. Kinetic and equilibrium data are compared with those for reaction with bases of 2,4,6-trinitrotoluene (TNT) and 1,3,5-trinitrobenzene. It is shown that the hypochlorite ion is not sufficiently basic to give a σ-adduct with 1,3,5-trinitrobenzene in aqueous methanol, and it is suggested that the coloured species produced during the reaction of TNT with sodium hypochlorite in aqueous methanol result from reaction of TNBCI, the initial product, with alkoxide ions. In the presence of micelles of hexadecyltrimethylammonium chloride TNT reacts with bases to give a σ-adduct, which is thought to be a Janovsky complex.