Tropos Diphenylmethane-Based Phosphine-Phosphoramidite Ligands: Design, Synthesis, and Application in Catalytic
Zhong Zheng1,2, Zheng-Chao Duan1, Xiang-Ping Hu2
1School of Chemical and Enviromental Engineering, Hubei Minzu University, Enshi 445000, China.
Abstract:
A series of chiral hybrid diphosphorus ligands incorporating a conformationally flexible tropos diphenylmethane-based phosphoramidite unit have been developed and evaluated in the Rh-catalyzed asymmetric hydrogenation of 2-(1-arylvinyl)anilides and α-enamides, leading to up to >99% yield and 99% enantiomeric excess. Preliminary results from comparative studies showcased the extraordinary catalytic performance of these chiral tropos phosphine-phosphoramidite ligands, with a competency essentially superior to those of well-established ligands with a regular rigid backbone.
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