Intramolecular 1,3-Dipolar Cycloaddition of Nitrile <i>N</i>-Oxide Accompanied by Dearomatization

Abstract

Intramolecular 1,3-dipolar cycloaddition of 2-phenoxybenzonitrile <i>N</i>-oxides to benzene rings, accompanied by dearomatization, formed the corresponding isoxazolines in high yields. The X-ray single-crystal structure analysis revealed that the reaction formed the <i>cis</i>-adduct as a single isomer. The substituents on the benzene rings markedly affected the reaction rate, yield, and structure of the final product