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2-Pyridinylboronic Acid MIDA Ester as a Stable 2-Pyridinyl Boron Anion Equivalent

By: Aaron Thornton, Chemfiles Volume 11 Article 1

The development of a viable air-stable surrogate for the notoriously unstable 2-pyridinylboronic acid has been a long-standing challenge in the field of cross-coupling. This motif is ubiquitous in drug-like small molecules, and therefore of particular importance to the synthetic community. While 2-pyridinylboronic acid surrogates exist, their use is often complicated by air- and moisture-sensitivity as well as their somewhat variable and impure compositions. In contrast, Burke and coworkers found that 2-pyridinyl MIDA boronate is isolable, benchtop and chromatography stable, and under slow-release conditions can be successfully coupled with a variety of aryl and heteroaryl chlorides (Table 1).


Table 1: Slow-release cross-coupling of 2-pyridinylboronic acid MIDA ester.(719390)

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Materials

     

References

  1. Gillis, E. P.; Burke, M. D. Aldrichimica Acta 2009, 131, 17.
  2. Knapp, D. M.; Gillis, E. P.; Burke, M. D. J. Am. Chem. Soc. 2009, 131, 6961.

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