Enantioselective imine hydrogenation with Ir diphosphine catalysts: fighting deactivation was written by Blaser, Hans-Ulrich;Pugin, Benoit;Spindler, Felix;Togni, Antonio. And the article was included in Comptes Rendus Chimie in 2002.Quality Control of (((4S,5S)-2,2-Dimethyl-1,3-dioxolane-4,5-diyl)bis(methylene))bis(diphenylphosphine) This article mentions the following:
While Ir diphosphine complexes are very active catalysts for the enantioselective hydrogenation of imines with good to excellent enantioselectivity, their deactivation is often a serious problem, leading to low catalyst productivity. Our study describes attempts to stabilize Ir catalysts with DIOP, BDPP and BPPM ligands for the hydrogenation of different imines. The best results were obtained with complexes immobilized on silica gel and with bimetallic W-Ir and Mo-Ir complexes. In most cases, enantiomeric excesses as well as initial rates were only slightly affected while the stability of the catalysts was enhanced significantly. In the experiment, the researchers used many compounds, for example, (((4S,5S)-2,2-Dimethyl-1,3-dioxolane-4,5-diyl)bis(methylene))bis(diphenylphosphine) (cas: 37002-48-5Quality Control of (((4S,5S)-2,2-Dimethyl-1,3-dioxolane-4,5-diyl)bis(methylene))bis(diphenylphosphine)).
(((4S,5S)-2,2-Dimethyl-1,3-dioxolane-4,5-diyl)bis(methylene))bis(diphenylphosphine) (cas: 37002-48-5) belongs to chiral phosphine ligands. During the past two decades, tertiary phosphine catalysts have been applied extensively in a wide range of carbon–carbon and carbon–heteroatom bond-forming transformations. Asymmetric catalytic performance is determined not only by the metal center but also by the chiral ligand selected.Quality Control of (((4S,5S)-2,2-Dimethyl-1,3-dioxolane-4,5-diyl)bis(methylene))bis(diphenylphosphine)
Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis