title: General synthesis of persistent trityl radicals for EPR imaging of biological systems.
abstract: In this paper we describe the syntheses of the tetraoxygenated triarylmethyl (trityl) radical 14 and the tetrathiatriarylmethyl (trityl) radicals 15 and 16. The syntheses include new and improved preparations of the key intermediate compounds 1 and 2. The new route to compound 2 is noteworthy for its efficiency and its avoidance of the highly toxic compound phosgene as well as the isolation of the air-sensitive 1,2,4,5-benzenetetrathiol.
authors.affiliation: Department of Chemistry, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, USA.
authors.forename: T Jagadeeswar
authors.initials: TJ
authors.lastname: Reddy
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Iwama
authors.forename: Howard J
authors.initials: HJ
authors.lastname: Halpern
authors.forename: Viresh H
authors.initials: VH
authors.lastname: Rawal
mesh_terms: D002384:Catalysis; D002625:Chemistry, Organic / Q000379:methods*; D004149:Dioxoles / Q000138:chemical synthesis* / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals / Q000737:chemistry; D006575:Heterocyclic Compounds, 3-Ring / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry; D010705:Phosgene / Q000737:chemistry; D012996:Solutions; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013696:Temperature; D014320:Triphenylmethyl Compounds / Q000737:chemistry*
chemical_list: C469849:1,2,4,5-benezenetetrathiol; C469848:2,2,6,6-tetramethylbenzo(1,2-d,4,5-d')bis(1,3)dioxole; C469847:2,2,6,6-tetramethylbenzo(1,2-d,4,5-d')bis(1,3)dithiole; D004149:Dioxoles; D005609:Free Radicals; D006575:Heterocyclic Compounds, 3-Ring; D010636:Phenols; D012996:Solutions; D013438:Sulfhydryl Compounds; D014320:Triphenylmethyl Compounds; D010705:Phosgene