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Updated: Aug 10, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
4,4'-Disubstituted BINAPs for highly enantioselective Ru-catalyzed asymmetric hydrogenation of ketones
Aiguo Hu1, Helen L Ngo, Wenbin Lin
1Department of Chemistry, CB#3290, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
Abstract:
A family of tunable precatalysts Ru(4,4'-BINAP)(chiral diamine)Cl2 was synthesized and used for highly enantioselective hydrogenation of aromatic ketones. This result differs from previous chiral diphosphines that rely on the bis(xylyl)phosphino groups to control enantioselectivity. An X-ray structural study reveals that the bulky substituents on the 4,4'-positions of BINAP can effectively create a suitable chiral pocket in the transition state and thus provide a new mechanism for the enantiocontrol in such a remarkable asymmetric catalytic process.
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