Effect of addition of phenols on the rate of Menschutkin reaction-Reaction , between phenacyl bromide and triethylamine

Abstract

432-436Second order rate constants for the reaction between phenacyl bromide and triethylamine with and without phenols have been determined in aprotic solvents at 25°, 30° and 35°C. The addition of X - C6H4 - OH (X= H, p-OCH3, p-CH3, p-CI, p-Br and p-NO2) with pKa greater than 7.15 does not affeqt the rate of quaternization of triethylamine by phenacyl bromide, whereas strong acidic phenols such as 2,4-dinitrophenol and 2,4,6-trinitrophenol do affect the rate of quaternization. pKa of phenol is found to be driving force for quaternization or protonation of triethylamine. The active nucleophiles in these processes are predicted