Asymmetric Hydrogenation of Seven-membered C=N-containing Heterocycles and Rationalization of the Enantioselectivity

Abstract

<p> Iridium(I) complexes of phosphine-phosphite ligands efficiently catalyze the enantioselective hydrogenation of diverse seven-membered C=N-containing heterocyclic compounds (eleven examples; up to 97% <em>ee</em>). P-OP ligand <strong>L3</strong>, which incorporates an <em>ortho</em>-diphenyl substituted octahydrobinol phosphite fragment, provided the highest enantioselectivities in the hydrogenation of most of the heterocyclic compounds studied. The observed sense of stereoselection was rationalized by means of DFT calculations.</p>