Oxidant-Free Au(I)-Catalyzed Halide Exchange and C(sp2)-O Bond Forming Reactions
Jordi Serra1, Christopher J Whiteoak1, Ferran Acuña-Parés1
1Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona , Campus de Montilivi, Girona E-17071, Catalonia, Spain.
Abstract:
Au has been demonstrated to mediate a number of organic transformations through the utilization of its π Lewis acid character, Au(I)/Au(III) redox properties or a combination of both. As a result of the high oxidation potential of the Au(I)/Au(III) couple, redox catalysis involving Au typically requires the use of a strong external oxidant. This study demonstrates unusual external oxidant-free Au(I)-catalyzed halide exchange (including fluorination) and Csp2-O bond formation reactions utilizing a model aryl halide macrocyclic substrate. Additionally, the halide exchange and Csp2-O coupling reactivity could also be extrapolated to substrates bearing a single chelating group, providing further insight into the reaction mechanism. This work provides the first examples of external oxidant-free Au(I)-catalyzed carbon-heteroatom cross-coupling reactions.
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