Kinetic and equilibrium studies of the proton and deuteron transfer reaction between diarylcyanomethanes and 1,2-bis-(dialkylaminomethyl)benzene in acetonitrile

Abstract

Equilibrium and rate constants, primary deuterium isotope effects, and activation parameters have been determined for the proton-transfer reactions of 4-nitrophenyl-phenyl-cyanomethane and 4-bromophenyl-4-nitrophenylcyanomethane with 1,2-bis(dimethylamino-methyl)benzene and 1,2-bis(diethylaminomethyl)benzene in acetonitrile. The reaction was followed spectrophotometrically using the stopped-flow technique. Large kinetic isotope effects at 25°C k H/ k D = 16.8 − 18.8 were observed for studied reactions. The multistep mechanism of the reactions was proposed.