title: Regiospecific syntheses of functionalized diaryliodonium tosylates via [hydroxy(tosyloxy)iodo]arenes generated in situ from (diacetoxyiodo)arenes.
abstract: Ready access to (18)F-labeled aryl synthons is required for preparing novel radiotracers for molecular imaging with positron emission tomography. Diaryliodonium salts react with cyclotron-produced no-carrier-added [(18)F]fluoride ion to produce [(18)F]aryl fluorides. We aimed to prepare functionalized diaryliodonium salts to serve as potential precursors for producing useful (18)F-labeled aryl synthons, such as (18)F-labeled halomethylbenzenes, benzaldehydes, and benzoic acid esters. Such salts were designed to have one functionalized aryl ring, one relatively electron-rich ring, such as 4-methoxyphenyl or 2-thienyl, and a nonfluorine containing weakly nucleophilic anion. Generation of a [hydroxy(tosyloxy)iodo]arene from a functionalized (diacetoxyiodo)arene in situ followed by treatment with an electron-rich arene, such as anisole or thiophene, or with a functionalized arylstannane gave expedient regiospecific access to a wide range of functionally diverse diaryliodonium tosylates in moderate to high yields (44-98%). The described methodology broadens the scope for producing new functionalized diaryliodonium salts for diverse applications.
authors.affiliation: Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Room B3 C346A, Building 10, 10 Center Drive, Bethesda, Maryland 20892-1003, USA.
authors.forename: Joong-Hyun
authors.initials: JH
authors.lastname: Chun
authors.forename: Victor W
authors.initials: VW
authors.lastname: Pike
mesh_terms: D001547:Benzaldehydes / Q000737:chemistry; D019817:Benzoic Acid / Q000737:chemistry; D004952:Esters / Q000737:chemistry; D005462:Fluorine Radioisotopes; D007462:Iodobenzenes / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009861:Onium Compounds / Q000138:chemical synthesis*; D049268:Positron-Emission Tomography; D013237:Stereoisomerism; D014105:Tosyl Compounds / Q000138:chemical synthesis*
chemical_list: D001547:Benzaldehydes; D004952:Esters; D005462:Fluorine Radioisotopes; D007462:Iodobenzenes; D009861:Onium Compounds; D014105:Tosyl Compounds; D019817:Benzoic Acid