Reactivity of Monochlorobenzene and Its Derivatives toward Solvated Electrons in Lower Aliphatic Alcohols

Monochlorobenzene and its para- or meta-substituted derivatives were irradiated with -γ-rays in methanol, ethanol and n-propanol containing nitrous oxide to elucidate the reactivities of these organic solutes toward solvated electrons, and also the effect of the substituent for the aromatic nucleus on the reactivities of these solutes. The value of G (N₂) is seen to decrease with increasing concentration of the organic solute. Relative rate constants of these organic solutes toward solvated electrons have been determined from the competition with nitrous oxide by observing the G(N₂) in there systems. Based on the results, the rate constants of the reactions of these derivatives of monochlorobenzene with solvated electrons relative to monochlorobenzene can be related to Hammett's σ function. The ρ value has been observed to be 3.3, 2.1 and 1.8 for methanol, ethanol and n-propanol respectively. The present data, together with that by Sherman⁽¹⁾ for 2-propanol, indicates that the ρ value is correlated linearly to the dielectric constant of the solvent. Some discussions are presented on the results thus obtained.