202405-42-3Relevant articles and documents
N-heterocyclic carbene complexes of Rh(I) and electronic effects on catalysts for 1,2-addition of phenylboronic acid to aldehydes
Tuerkmen, Hayati,Cetinkaya, Bekir
experimental part, p. 226 - 232 (2012/04/17)
1,3-Diarylsubstituted imidazolinium salts, (NHC-H)Cl, 3, containing hydrogen or alkyl groups at the 4,5-positions of the imidazolidine ring, served as precursors to rhodium(I) complexes [RhCl(NHC)COD], 4, which were converted into cis-[RhCl(NHC)(CO)2] complexes, 5. All compounds prepared were characterized by elemental analyses, 1H NMR and 13C NMR. The relative σ-donor/π-acceptor strength of the NHC ligands was determined by means of IR spectroscopy of 5. The ability of NHCs in 4 to enchance activity was explored in the 1,2-addition of phenylboronic acid to aldehydes. A good correlation was observed between catalytic activity and the electron-donating power of the NHC ligands.