Synthesis and characterization of FePd magnetic nanoparticles modified with chiral BINAP ligand as a recoverable catalyst vehicle for the asymmetric coupling reaction

Phys Chem Chem Phys. 2009 Oct 21;11(39):8949-54. doi: 10.1039/b910069e. Epub 2009 Jul 30.

Abstract

The initial thermal decomposition of iron carbonyl (Fe(CO)(5)), followed by reduction of palladium acetylacetonate (Pd(acac)(2)) produced FePd nanoparticles (NPs) with an Fe(x)O(y)-rich core and a Pd-rich shell. The as-synthesized NPs were subsequently treated with (S)-2,2'-bis(diphenylphosphino)-1,1'-binaphthene ((S)-BINAP) as a chiral modifier, which provides them with the optical activity to show a negative Cotton effect in the circular dichroism (CD) spectrum. Characterization by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), superconducting quantum interface device (SQUID) and X-ray absorption fine structure (XAFS) measurements was performed. The FePd NPs modified with (S)-BINAP had a mean diameter of ca. 5.6 nm, and exhibited superparamagnetic behavior at 300 K with zero remanence and coercivity. The FePd-(S)-BINAP was shown to catalyze the asymmetric Suzuki-Miyaura coupling reaction with easy recovery from the reaction mixture by applying an external magnet. The designed architecture enabled the powerful combination of two functionalities, magnetism that responds to a magnetic field for easy recycling, as well as an optically active catalytic center that promotes the asymmetric coupling reaction.

MeSH terms

  • Catalysis
  • Iron / chemistry*
  • Ligands
  • Magnetics*
  • Molecular Structure
  • Nanoparticles / chemistry*
  • Naphthalenes / chemical synthesis
  • Naphthalenes / chemistry*
  • Palladium / chemistry*
  • Particle Size
  • Surface Properties

Substances

  • BINAP, 2-naphthol
  • Ligands
  • Naphthalenes
  • Palladium
  • Iron