Synfacts 2007(4): 0363-0363  
DOI: 10.1055/s-2007-968373
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart · New York

Asymmetric Hydrogenation of Quinolines

Contributor(s): Victor Snieckus, Todd Macklin
W.-J. Tang, S.-F. Zhu, L.-J. Xu, Q.-L. Zhou, Q.-H. Fan, H.-F. Zhou, K. Lam, A. S. C. Chan*
Hong Kong Polytechnique University; Nankai University, Tianjin and The Chinese Academy of Sciences, Beijing, P. R. of China
Further Information

Publication History

Publication Date:
23 March 2007 (online)

Significance

Reported is the use of a highly active and stable chiral spirobiindane phosphinite ligand (L) for the asymmetric hydrogenation of quinolines which proceeds with good enantio­selectivities and complete conversions. Substrate/catalyst (S/C) ratios up to 5000 and initial TOF of 2400 h-1 have been achieved, the latter being the best so far reported for this reaction. The Ir complex can be stored in THF for two months with no loss of activity and the solvent can be modified for catalyst recycling using a DMPEG-500/hexanes biphasic system with minimal loss in enantioinduction after five runs, albeit a 60% drop in conversion.