Chiral phosphine-phosphoramidite ligands for highly efficient Ir-catalyzed asymmetric hydrogenation of sterically hindered N-arylimines.
نویسندگان
چکیده
A mild and general iridium-catalyzed, highly enantioselective hydrogenation of sterically hindered N-arylimines with a new H(8)-BINOL-derived phosphine-phosphoramidite ligand has been developed. The present catalytic system features high turnover numbers (up to 100000) and good to perfect enantioselectivities (up to 99% ee) for the hydrogenation of a variety of sterically hindered N-arylimines.
منابع مشابه
Monodentate, Supramolecular and Dynamic Phosphoramidite Ligands Based on Amino Acids in Asymmetric Hydrogenation Reactions Breuil, P.A.R
The electronic and steric effects as well as hydrogen bonds on the formation of the heteroligand complexes between monodentate amino acid based phosphoramidite and monodentate phosphine ligands were studied. Pure heterocomplex formation through the hydrogen bond between LEUPhos and a urea based phosphine is observed leading to highly active and selective catalyst. Substrate orientation through ...
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عنوان ژورنال:
- Organic letters
دوره 14 13 شماره
صفحات -
تاریخ انتشار 2012