Mechanistic studies in strongly basic media. Part IV. Proton removal from 4-nitrodiphenylmethyl chloride by sodium and potassium t-butoxides in t-butyl alcohol

Abstract

Rates of proton abstraction from the α-carbon atom of 4-nitrodiphenylmethyl chloride in solutions of sodium and potassium t-butoxides in t-butyl alcohol at 30° have been measured spectrophotometrically. For a given concentration of base, the rate of attainment of equilibrium is faster when potassium is the counter-ion than when sodium t-butoxide is used. However, rates of proton abstraction in media having a given value of the indicator acidity function H_r^BuOH are independent of the nature of the cation. Mechanistic implications of the results are discussed.