117409-06-0Relevant academic research and scientific papers
Asymmetric Catalysis, 45. - Enantioselective Hydrosilylation of Ketones with 2/Pyridinyloxazoline Catalysts
Brunner, Henri,Obermann, Uwe
, p. 499 - 508 (2007/10/02)
21 optically active 2-(2-pyridinyl)oxazolines are synthesized from 2-cyanopyridine and optically pure amino alcohols.The new pyridinyloxazolines are used as cocatalysts together with 2 as homogeneous in situ catalysts in the enantioselective hydrosilylation of prochiral ketones with diphenylsilane.After hydrolysis, 1-phenylethanol is produced in 83.4percent ee from acetophenone.Another three ketones are included into these investigations.The optical purity depends on the rhodium/ligand, rhodium/ketone, and ketone/silane ratio as well as on the solvent.Compared with other organic solvents, hydrosilylations in the solvent CCl4 without exceptions result in better chemical yields and optical purities as consequence of a change in the catalytically active species due to oxidative addition of CCl4. - Keywords: Enantioselective hydrosilylation/ Optically active secondary alcohols/ Rhodium/ pyridinyloxazoline catalysts
ENANTIOSELECTIVE HYDROSILYLATION OF ACETOPHENONE WITH RHODIUM /OXAZOLINES CATALYSTS
Balavoine, G.,Clinet, J.C.,Lellouche, I.
, p. 5141 - 5144 (2007/10/02)
N-chelate ligands based on chiral oxazolines are efficient co-catalysts in the enantioselective hydrosilylation of acetophenone with α-naphtylphenylsilane.Enantiomeric excess as up to 80percent have been achieved.
