Highly efficient palladium precatalysts of homoscorpionate bispyrazolyl ligands for the more challenging Suzuki-Miyaura cross-coupling of aryl chlorides

Dalton Trans. 2010 Aug 21;39(31):7353-63. doi: 10.1039/c003174g. Epub 2010 Jul 6.

Abstract

Highly efficient palladium precatalysts {[RN{-(CH(2))(n)-pz(3,5-Me)(2)}(2)]PdCl(2)}(m) [m = n = 1; R = 2,6-Me(2)C(6)H(3) (1), 2,4,6-Me(3)C(6)H(2) (2), CH(2)Ph (3) and m = n = 2; R = CH(2)Ph (4)] of a series of homoscorpionate bispyrazolyl ligands for the Suzuki-Miyaura cross-coupling of the more challenging aryl chloride substrates are reported. In particular, the palladium 1-4 precatalysts carried out the Suzuki-Miyaura cross-coupling of a wide variety of aryl chloride substrates bearing electron withdrawing, electron donating and heteroaryl substituents. Remarkably enough, the molecular structure determination of the 1-4 precatalysts by X-ray diffraction studies revealed the presence of anagostic [C-H...Pd] type interactions in the mononuclear 1-3 complexes of methylene bridged bispyrazolyl ligands whereas the ethylene bridged analog 4 yielded an interesting dimeric 20-membered macrometallacyclic complex devoid of any such interaction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzyl Compounds / chemistry*
  • Catalysis
  • Coordination Complexes / chemical synthesis
  • Coordination Complexes / chemistry*
  • Crystallography, X-Ray
  • Ligands
  • Molecular Conformation
  • Palladium / chemistry*
  • Pyrazoles / chemistry*
  • Quantum Theory

Substances

  • Benzyl Compounds
  • Coordination Complexes
  • Ligands
  • Pyrazoles
  • Palladium
  • benzyl chloride