Evidence for rate-limiting deprotonation of a spiro-Meisenheimer intermediate during Smiles' rearrangement of 2-(p-nitrophenoxy)ethylamine

Abstract

Kinetic studies of intramolecular nucleophilic aromatic displacement of alkoxide ion by the amino group in 2-(p-nitrophenoxy)ethylamine support a mechanism whereby, at low base concentrations, the rate of Smiles' rearrangement is dependent upon the rate of general base-catalysed deprotonation of a spiro-Meisenheimer intermediate; at high base concentrations the base independent rate of formation of the Meisenheimer intermediate becomes rate limiting.