Tropos Diphenylmethane-Based Phosphine-Phosphoramidite Ligands: Design, Synthesis, and Application in Catalytic Asymmetric Hydrogenation

Org Lett. 2025 Jan 9. doi: 10.1021/acs.orglett.4c04503. Online ahead of print.

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.