Monodentate, Supramolecular and Dynamic Phosphoramidite Ligands Based on Amino Acids in Asymmetric Hydrogenation Reactions Breuil, P.A.R
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چکیده
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 a hydrogen bond between the alcohol group of the substrate and the ester moiety of the phosphoramidite is suggested to play a crucial role in achieving the excellent selectivities. * This work has been published: P.-A. R. Breuil, F. W. Patureau, J. N. H. Reek, Angew. Chem. Int. Ed. 2009, 48, 12, 2162-2165. Singly Hydrogen Bonded Supramolecular Ligands for the Rhodium-Catalyzed Hydrogenation
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