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Ligand-Enabled Reactivity and Selectivity in a Synthetically Versatile Aryl C–H Olefination

Ligand-Enabled Reactivity and Selectivity in a Synthetically Versatile Aryl C–H Olefination

  1. Anonymous
    Dong-Hui Wang, Keary M. Engle, Bing-Feng Shi, Jin-Quan Yu*

    Sciencexpress

    The Mizoroki-Heck reaction, which couples aryl halides
    with olefins, has been widely used to stitch together the
    carbogenic cores of numerous complex organic molecules.
    Given that the position-selective introduction of a halide
    onto an arene is not always straightforward, direct
    olefination of aryl C–H bonds would obviate the
    inefficiencies associated with generating halide precursors
    or their equivalents; however, methods for carrying out
    such a reaction have suffered from narrow substrate
    scope and low positional selectivity. Here we report an
    operationally simple, atom-economical, carboxylatedirected
    Pd(II)-catalyzed C–H olefination reaction with
    phenylacetic acid and 3-phenylpropionic acid substrates,
    using oxygen at atmospheric pressure as the oxidant. The
    positional selectivity can be tuned by introducing amino
    acid derivatives as ligands. We demonstrate the versatility
    of the method through direct elaboration of commercial
    drug scaffolds and efficient synthesis of 2-tetralone and
    naphthoic acid natural product cores.