Rhodium-catalyzed enantioselective hydrogenation of (1-arylvinyl)phosphonates with TADDOL-based phosphoramidite P,S ligands

A series of readily available modular chiral P,S-bidentate TADDOL-based phosphoramidites were evaluated in the Rh(I)-catalyzed hydrogenation of α,β-unsaturated phosphonates. The Rh(I)-L3 catalyst was revealed to be highly effective for a wide variety of diisopropyl (1-arylvinyl)phosphonates, producing the corresponding (1-arylethyl)phosphonates under mild conditions with low catalyst loading (up to 0.2 mol%) and overall excellent enantiocontrol (up to 99% ee).