The stabilities of Meisenheimer complexes. Part 26. The reactions of some aromatic nitro-compounds with base in t-butyl alcohol–water mixtures

Abstract

Kinetic and equilibrium data are reported for the reaction of three nitro-compounds with tetramethylammonium hydroxide in t-butyl alcohol containing water. In all solvent systems studied the reactive nucleophile is thought to be the hydroxide ion rather than the t-butoxide ion. The reaction of 1,3,5-trinitrobenzene with base gives a σ-adduct, while 1-chloro-2,4-dinitrobenzene gives 2,4-dinitrophenol. The rates of both these reactions fall rapidly with increasing water in the solvent. In contrast the rate of formation of picric acid from the third substrate, picryl chloride, increases with water content due to the initial formation of the 3-hydroxy-adduct.