title: Synthesis and characterization of cationic selenium-nitrogen heterocycles from tert-butyl-DAB (DAB = 1,4-di-tert-butyl-1,3-diazabutadiene) and SeX4 via the reductive elimination of X2 (X = Cl, Br): a distinct contrast with tellurium.
abstract: The synthesis and comprehensive characterisation of a series of 1,2,5-selenadiazolium salts, which were generated from the direct reaction between the neutral bidentate ligand tert-butyl-DAB and a variety of heavy chalcogen halides, are reported. The formation of the cationic heterocycle from the reaction of SeX4 (X = Cl, Br) and the ligand results in a two electron redox process where the chalcogen undergoes a two electron reduction concomitant with the elimination of X2, the oxidation by-product. A reaction pathway for this chemistry has been proposed necessitating several key intermediates. These species have been synthesized and used in a stepwise series of transformations that strongly supports this very unusual reactivity for the chalcogens. In contrast, the reaction between tert-butyl DAB and TeX4 (X = Cl, Br, I), does not result in redox, rather an octahedral Te(iv) x DAB complex is formed or no reaction was observed.
authors.affiliation: Department of Chemistry, The University of Western Ontario, 1151 Richmond St., London, Ontario, Canada.
authors.forename: Jason L
authors.initials: JL
authors.lastname: Dutton
authors.forename: Andre
authors.initials: A
authors.lastname: Sutrisno
authors.forename: Robert W
authors.initials: RW
authors.lastname: Schurko
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Ragogna