Applications of magnetic Fe2O3 nanoparticles in organic chemistry

COLL 234

Guifeng Li, guifeng@mtholyoke.edu, Philip Stevens, stevensphilip@yahoo.com, and Yong Gao, ygao@chem.siu.edu. Department of Chemistry and Biochemistry, Southern Illinois University, 1245 Lincoln Drive, Carbondale, IL 62901
The application of magnetic Fe2O3 nanoparticles as a scaffold for hosting catalysts was investigated. N-Heterocyclic carbene (NHC) moieties were immobilized onto the surface of Fe2O3 nanoparticles through a silane linker. Subsequently, nanoparticles were functionalized by the formation of NHC-Pd complexes. The nanoparticle-supported NHC-Pd catalysts demonstrated high catalytic activity in cross-coupling reactions. The recovery of catalysts was easily achieved by using an external magnet. No significant loss of the catalytic activity of the immobilized catalysts was observed after five rounds of reactions. More importantly, a comparative kinetic study of coupling reactions promoted by palladium catalysts that are supported by insoluble polymer support, nanoparticle support, and non-support proved that the catalytic activity of Fe2O3 nanoparticle-supported NHC-Pd was greatly enhanced.