A New Furan Synthesis. Evidence for the Intermediacy of the Elusive Anhydro-5-hydroxy-1,3-dioxolium Hydroxide System

Abstract

While five-membered mesoionic ring systems have been employed as useful synthetic intermediates in the preparation of a wide variety of pyrroles and thiophenes¹, only limited application has been made to the preparation of furans². We would like to report a new furan synthesis in which the unreported anhydro-5-hydroxy-1, 3-dioxolium hydroxide system may be an intermediate.