1,3-Dinitrobenzene – hydroxide ion interactions. Equilibrium constants for σ-complex formation in the dimethylformamide–water solvent system

Abstract

ERWIN BUNCEL and ALLEN W. ZABEL. Can. J . Chem. 59, 3168 (1981). The results of a uv-visible spectroscopic study of the interaction of 1,3-dinitrobenzene (DNB) with hydroxide ion in aqueous dimethylformamide (DMF) media are reported. Formation of several spectral species has been discerned, depending on factors such as the relative concentrations of the reactants, the time scale of the experiments, and the medium composition. The principal interaction is formation of the I-hydroxy-2,4-dinitrocyclohexadienate anion. The molar absorptivities of this o-complex, and the equilibrium constants (K,) for its formation, have been determined as a function of medium composition. Values of K, increase from 7.5 M

Kinetics of ionisation of carbon acids in non-aqueous media: detritiation of [2-3H1]diethyl malonate by heterocyclic bases

“…Hydrogen isotope exchange is particularly suited for studying proton transfer from carbon acids under a variety of conditions, for example as catalyzed by acids, bases and metal ions (7)(8)(9)(10)(11)(12), but in the past such investigations have also been largely limited to aqueous media. In this paper we report on the development of two procedures which have general applicability for measurement of detritiation rates of carbon acids in non-aqueous media.…”

Ambident nucleophilic reactivity in σ-complex formation. Part 5. Reaction of 1-phenyl-2,4,6-trinitrobenzene with methoxide and phenoxide ions

“…As part of a continuing study on the interactions of nitroaromatic compounds with bases (1)(2)(3), in this paper we present results pertaining to the formation of 1,l and 1,3 a-complexes and the ambident reactivity of phenoxide ion (4).…”