title: Highly efficient synthesis and solid-state characterization of 1,2,4,5-tetrakis(alkyl- and arylamino)benzenes and cyclization to their respective benzobis(imidazolium) salts.
abstract: [reaction: see text] New synthetic methodology to a variety of 1,2,4,5-tetraaminobenzenes and their corresponding benzobis(imidazolium) salts has been accomplished. Palladium-catalyzed coupling of various 1,2,4,5-tetrabromo- or 1,2,4,5-tetrachlorobenzenes with aryl- or tert-alkylamines afforded the respective tetrakis(N-substituted)aminobenzenes in excellent yields. This enabled comparative solid-state structural analyses of this elusive class of electron-rich arenes with their oxidized derivatives. The tetraamines were found to undergo formylative cyclization to the corresponding benzobis(imidazolium) salts in good to excellent yields.
authors.affiliation: Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Dimitri M
authors.initials: DM
authors.lastname: Khramov
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Boydston
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Bielawski
mesh_terms: D001555:Benzene Derivatives / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D018360:Crystallography, X-Ray; D003500:Cyclization; D007093:Imidazoles / Q000138:chemical synthesis* / Q000737:chemistry; D008968:Molecular Conformation; D015394:Molecular Structure; D012492:Salts / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D001555:Benzene Derivatives; D007093:Imidazoles; D012492:Salts