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Updated: Jul 18, 2026

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Stereochemistry of imine reduction by a hydroxycyclopentadienyl ruthenium hydride
Charles P Casey1, Galina A Bikzhanova, Ilia A Guzei
1Department of Chemistry, University of Wisconsin, Madison, WI 53706, USA. casey@chem.wisc.edu
Abstract:
The stereochemistry of hydrogen transfer from [2,5-Ph(2)-3,4-Tol(2)(eta(5)-C(4)COD)]Ru(CO)(2)D to N-aryl imines to give amine complexes was shown to be mostly trans stereospecific. Stereospecific hydrogen transfer is proposed to generate an amine and a coordinatively unsaturated ruthenium intermediate in close proximity. Coordination of the amine is proposed to occur faster than lone pair inversion of the amine. In contrast, hydrogen transfer to N-alkyl imines is stereorandom. It is proposed that stereochemistry is lost in part due to the reversibility of the hydrogen transfer being faster than amine coordination.
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