Kinetics and isotope effects ort the proton transfer reaction of 4-nitrophenylphenylcyanomethane with tetramethylguanidine in acetonitrile and benzonitrile solvents

A Jarczewski, P Pruszynski…

Index: Jarczewski, Arnold; Pruszynski, Przemyslaw; Leffek, Kenneth T. Canadian Journal of Chemistry, 1983 , vol. 61, p. 2029 - 2032

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Citation Number: 21

Abstract

The kinetic deuterium isotope effect for the proton transfer reaction between 4- nitrophenylphenylcyanomethane and tetramethylguanidine, k H/k D, at 25° C, is 10.7 in acetonitrile solvent and 12.5 in benzonitrile. The enthalpy of activation difference,, in both solvents is large, 2.2 kcal mol-1, and 2.4 kcal mol-1; respectively, indicating a significant contribution from proton tunnelling to the reaction. The equilibrium constants, K, measured ...