Cyclic Diaryl λ3 -Bromanes as Original Aryne Precursors
Matteo Lanzi1, Quentin Dherbassy1, Joanna Wencel-Delord1
1Laboratoire d'Innovation Moléculaire et Applications (UMR CNRS 7042), Université de Strasbourg/Université de Haute Alsace, ECPM, 25 rue Becquerel, 67087, Strasbourg, France.
Abstract:
Despite the widespread application of hypervalent iodines, the corresponding λ3 -bromanes are less explored. Herein we report a general, safe, and high-yielding strategy to access cyclic diaryl λ3 -bromanes. These unique compounds feature reactivity that is appealing and complementary to that of λ3 -iodanes, generating arynes under mild reaction conditions and in the presence of a weak base. Accordingly, formal meta-selective transition-metal-free C-O and C-N couplings may be achieved. Mechanistic studies unambiguously support the aryne generation mechanism.
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