Elimination of 3-Hydroxy-2-nitro-2, 3-dihydrobenzo[b]furans to 2-Nitrobenzo[b]furans

Abstract

β-Elimination of stereoisomeric cis- and trans-3-hydroxy-2-nitro-2, 3-dihydrobenzo[b]furans was investigated. The 2, 3-dihydrobenso[b]furans were stable under acidic conditions but were easily dehydrated under basic conditions to afford the corresponding 2-nitrobenzo[b]furans. An (ElcB)_R mechanism is proposed on the basis of several lines of evidence obtained from studies on kinetics, ultraviolet spectra, leaving group effect and deuterium isotope effect in the elimination reaction.