posted on 2021-05-06, 14:35authored byAlexander
J. Shumski, William A. Swann, Nicole J. Escorcia, Christina W. Li
Directed
hydrogenation, in which product selectivity is dictated
by the binding of an ancillary directing group on the substrate to
the catalyst, is typically catalyzed by homogeneous Rh and Ir complexes.
No heterogeneous catalyst has been able to achieve equivalently high
directivity due to a lack of control over substrate binding orientation
at the catalyst surface. In this work, we demonstrate that Pd–Cu
bimetallic nanoparticles with both Pd and Cu atoms distributed across
the surface are capable of high conversion and diastereoselectivity
in the hydroxyl-directed hydrogenation reaction of terpinen-4-ol.
We postulate that the OH directing group adsorbs to the more oxophilic
Cu atom while the olefin and hydrogen bind to adjacent Pd atoms, thus
enabling selective delivery of hydrogen to the olefin from the same
face as the directing group with a 16:1 diastereomeric ratio.