Chiral paramagnetic closo-ruthenacarboranes via phosphine-diphosphine displacement reaction of “three-bridge” exo-nido-ruthenacarboranes: Molecular Structure of (-)-[closo-3-Cl-3,3-{(Ph2PCHCH3)2CH2}-3,1,2-RuC2B9H11] and its ortho-cycloboronated derivative was written by Cheredilin, Dmitri N.;Kadyrov, Renat;Dolgushin, Fedor M.;Balagurova, Elena V.;Godovikov, Ivan A.;Solodovnikov, Stanislav P.;Chizhevsky, Igor T.. And the article was included in Inorganic Chemistry Communications in 2005.SDS of cas: 77876-39-2 This article mentions the following:
Ruthenacarboranes with chiral non-racemic (2S,4S)-2,4-bis(diphenylphosphino)pentane ligand were prepared by ligand substitution and cage closing of ruthenium nido-carborane complexes. Treatment of [exo-nido-[Cl(Ph3P)2Ru]-(μ-H)3-10-H-7,8-C2B9H8] (1) with the (2S,4S)-(-)-2,4-bis(diphenylphosphino)pentane (3, BDPP) in toluene results in the formation of three novel optically active diphosphine-ruthenium closo complexes, 18e diamagnetic (-)-[closo-3-Cl-3,3-[(S,S)-BDPP]-3-H-3,1,2-RuC2B9H11] (4), and 17e paramagnetic (-)-[closo-3-Cl-3,3-[(S,S)-BDPP]-3,1,2-RuC2B9H11] (5) along with its ortho-cycloboronated derivative (-)-[closo-3-Cl-3,3-[(S,S)-Ph2PCH(CH3)CH2CH(CH3)PPh-ortho-C6H4]-3,1,2-RuC2B9H10] (6). Both odd-electron complexes 5 and 6 were characterized by single-crystal x-ray diffraction anal. In the experiment, the researchers used many compounds, for example, (2S,4S)-Pentane-2,4-diylbis(diphenylphosphine) (cas: 77876-39-2SDS of cas: 77876-39-2).
(2S,4S)-Pentane-2,4-diylbis(diphenylphosphine) (cas: 77876-39-2) belongs to chiral phosphine ligands. Although many reactions require more nucleophilic trialkylphosphines as catalysts, only a few chiral trialkylphosphines are available. Indeed, very little research on chiral tertiary phosphine-catalyzed asymmetric reactions occurred prior to the year 2000.SDS of cas: 77876-39-2
Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis