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Technology Spotlights

2nd Generation Buchwald Precatalysts

Buchwald precatalysts and ligands are bulky electron-rich dialkylbiaryl phospine-based catalysts and structurally related ligands that improve reactivity in Pd-catalyzed cross - coupling reactions. These highly active reagents have been extensively applied in the synthesis of pharmaceuticals, natural products, polymers, and new materials.

The structure of the dialkylbiaryl ligand plays an important role in the efficiency of the catalysts (Figure 1). Aldrich Chemistry offers a wide range of new and diverse Buchwald ligands for various synthetic applications.







Buchwald precatalysts have the widest scope for Pd-catalyzed C–C, and C–N bond formation. We have introduced a new class of 2nd generation XPhos precatalysts where the parent aliphatic amine is replaced by the more reactive 2-aminobiphenyl (lower pKa) (Figure 2).








The key features for precatalysts:

  • Air stable
  • Highly efficient
  • Utilized under mild conditions
  • Short reaction times
  • Low catalyst loadings

 




Buchwald and coworkers have reported the use of 2nd generation XPhos precatalysts (Cat. No. 741825) in the Suzuki cross-coupling of unstable polyfluorophenyl and five-membered 2-heterocyclic boronic acids with aryl halides in excellent yields.

 





Suzuki Coupling of Polyfluoroboronic Acids






Cat. No. 741825







Suzuki Coupling of Heterocyclic Boronic Acids


 

 

References:

  1.  Surry, D. S.; Buchwald, S. L. Chem. Sci. . 2011, 2, 27.
  2.  Martin, R.; Buchwald, S. L. Acc. Chem. Res. . 2008, 41, 1461.
  3.  Surry, D. S.; Buchwald, S. L. Angew. Chem. Int. Ed. . 2008, 47, 6338.
  4.  Kinzel, T; Zhang, Y.; Buchwald, S. L. J. Am. Chem. Soc. . 2010, 132, 14073.

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