Asymmetric olefin hydrogenation with Rh complexes with unsymmetrical diphosphorus ligands

Abstract

In this project, rhodium(I) complexes C1–C3 bearing ligands L1–L3 were intended to be used in the asymmetric hydrogenation of substrates S1–S12. Complexes C1 and C2, of the type [Rh(COD)(L)]BF4, were prepared in a previous project, while complex C3 was prepared from ligand L3. Ligand L3 has been synthesized from methylphosphine–borane P3 and fully characterized, while complex C3 could only be partially characterized due to the covid19 pandemic. It has been observed that C3 is a bischelated complex that tends to oxidize in solution. In the future, the synthesis of C3 will be repeated under stricter inert atmosphere. Also due to the confinement against covid19, the hydrogenation of substrates S1–S12 has not been possible, and instead a literature search of hydrogenation results with similar ligands has been made.