Investigations into the mechanism of the in situ formation of neutral dinuclear rhodium complexes was written by Moeller, Saskia;Kubis, Christoph;Drexler, Hans-Joachim;Alberico, Elisabetta;Heller, Detlef. And the article was included in Journal of Organometallic Chemistry in 2019.Electric Literature of C31H32O2P2 This article mentions the following:
The often applied in situ formation of neutral dinuclear rhodium precatalysts of the type [Rh(Diphosphine)(μ2-Cl)]2 with the ligands DPEPhos and DIOP has been mechanistically investigated by NMR spectroscopy. The structural characterization of reaction intermediates [Rh2(μ2-Diphosphine)(COD)2(Cl)2] and [Rh2(Diphosphine)(COD)(μ2-Cl)2] was accomplished using x-ray crystallog. So a new and unexpected intermediate was found, which casts a new light on the mechanism of this ligand exchange. In addition, equilibrium could be found which can at least influence the formation of neutral dinuclear rhodium precatalysts. 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: 37002-48-5Electric Literature of C31H32O2P2).
(((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. Chiral phosphine catalysts: Nucleophilic phosphine catalysis often involves the formation of Lewis adducts, namely phosphonium (di)enolate zwitterions, as reaction intermediates.Electric Literature of C31H32O2P2
Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis