108915-10-2Relevant academic research and scientific papers
Synthesis of Optically Active Bis(2-oxazolines): Crystal Structure of a 1,2-Bis(2-oxazolinyl)benzene * ZnCl2 Complex
Bolm, Carsten,Weickhardt, Konrad,Zehnder, Margareta,Ranff, Tobias
, p. 1173 - 1180 (2007/10/02)
Dinitriles (5-7, 12, 13) react with enantiomerically pure β-amino alcohols (8-11, 17) under zinc chloride catalysis to give optically active C2-symmetric bis(oxazolines). 1,2-Bis(2-oxazolin-2-yl)benzenes 1a-e are obtained under mild reaction conditions. 1H-NMR spectroscopy indicates the formation of 1:1 complexes 23 of these compounds with ZnCl2.The energy required for a conformational interconversion of zinc dichloride complex 23e was determined by variable-temperature 1H-NMR studies.An X-ray structure analysis was performed with the substituted zinc dichloride complex 23a.
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
