Kinetic and equilibrium studies of the σ-adduct forming reactions of 1,3,5-trinitrobenzene and picryl chloride with some carbon bases

Abstract

Reaction of 1,3,5-trinitrobenzene (TNB) with the malononitrile anion in methanol yields a carbon-bonded σ-adduct, (3). Ionisation of the remaining exocyclic hydrogen is favourable and yields the dianion (4). The initial reaction of 1-chloro-2,4,6-trinitrobenzene similarly occurs at an unsubstituted ring position, but is followed by slower nucleophilic attack at the 1-position yielding the substituted product. A major difference in the reaction of the ethyl malononitrile anion with TNB is that the adduct formed (11) has no readily dissociable proton. Hence, here, conversion to the carbon-bonded adduct is less favourable. Kinetic and equilibrium data are reported for these reactions and are compared with data for adduct formation involving methoxide ions.