title: Copper-mediated fluorination of arylboronate esters. Identification of a copper(III) fluoride complex.
abstract: A method for the direct conversion of arylboronate esters to aryl fluorides under mild conditions with readily available reagents is reported. Tandem reactions have also been developed for the fluorination of arenes and aryl bromides through arylboronate ester intermediates. Mechanistic studies suggest that this fluorination reaction occurs through facile oxidation of Cu(I) to Cu(III), followed by rate-limiting transmetalation of a bound arylboronate to Cu(III). Fast C-F reductive elimination is proposed to occur from an aryl-copper(III)-fluoride complex. Cu(III) intermediates have been generated independently and identified by NMR spectroscopy and ESI-MS.
authors: Department of Chemistry, University of California, Berkeley, California 94720, USA.
authors: Patrick S
authors: PS
authors: Fier
authors: Jingwei
authors: J
authors: Luo
authors: John F
authors: JF
authors: Hartwig
mesh_terms: D001897:Boronic Acids / Q000737:chemistry*; D002384:Catalysis; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D004952:Esters / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D054879:Halogenation; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry
chemical_list: D001897:Boronic Acids; D056831:Coordination Complexes; D004952:Esters; D010165:Palladium; D003300:Copper; D005459:Fluorides
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