title: Verdazyl radicals as substrates for organic synthesis: a synthesis of 3-methyl-5-aryl-1,3,4-oxadiazolones.
abstract: The synthesis of oxadiazolones under hydrolytic conditions is described for a series of 3-methyl-5-aryl-1,3,4-oxadiazolone compounds. The unique starting materials for the hydrolysis reaction are obtained from efficient 1,3-dipolar cycloaddition reactions of styrene and azomethine imine dipoles derived from verdazyl radicals via a disproportionation reaction. A proposed mechanism for the formation of these biologically relevant oxadiazolones includes an opening of the tetrazinone ring followed by a 5-exo-trig ring closure. In support of the mechanism, in one case the ring-opened intermediate was isolated and subsequently treated with acid to give the relevant oxadiazolone.
authors.affiliation: Department of Chemical and Physical Sciences, University of Toronto at Mississauga, 3359 Mississauga Road, Mississauga, Ontario, Canada L5L 1C6.
authors.forename: Matthew
authors.initials: M
authors.lastname: Bancerz
authors.forename: Michael K
authors.initials: MK
authors.lastname: Georges