Yasui, Takeshi; Nakazato, Yuya; Kurisaki, Koutarou; Yamamoto, Yoshihiko published the artcile< Enantioselective Construction of 5-6-5 Tricyclic Lactone Framework Bearing a Quaternary Bridgehead Carbon via Rh-Catalyzed Asymmetric [2+2+2] Cycloaddition of Enediynes>, Name: (S)-(-)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is tricyclic cyclohexadiene lactone preparation enantioselective; enediyne cycloaddition rhodium catalyst.
Herein, a Rh-catalyzed asym. [2+2+2] cycloaddition of ene-yne-yne enediynes to generate enantio-enriched tricyclic cyclohexadienes bearing a quaternary bridgehead carbon is reported. The Rh-Phanephos complex is an appropriate catalyst for the cycloaddition of enediynes bearing an unsubstituted propiolate terminus, whereas Rh-biaryl bisphosphine catalysts, which have been widely used for asym. cycloadditions of alkynes and alkenes, are not applicable for the reaction of such enediynes. Several control experiments suggest that the reaction using the Rh-Phanephos complex exclusively proceeds via a rhodacyclopentadiene intermediate, unlike when using a Rh-biaryl bisphosphine complex that can form a rhodacyclopentadiene intermediate as well as a rhodacyclopentene intermediate in a substrate-dependent manner.
Advanced Synthesis & Catalysis published new progress about [2+2+2] Cycloaddition reaction (stereoselective). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Name: (S)-(-)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl.
Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate