A new chiral phosphine-phosphoramiditeligand (S)-HY-Phos 1 has been prepared from 1-naphthylamine via a two-step transformation, and successfully applied in the Rh-catalyzed asymmetrichydrogenation of various functionalized olefins, including α-(acetamido)cinnamates, enamides and α-enol ester phosphonates, in which up to 98% ee, 99% ee and 99% ee were achieved, respectively.
Tuning of the Structures of Chiral Phosphane-Phosphites: Application to the Highly Enantioselective Synthesis of α-Acyloxy Phosphonates by Catalytic Hydrogenation
ligands 1 and 5 in catalytic asymmetric hydrogenations of enolphosphonates 12 demonstrated a critical influence of the steric characteristics of the phosphane-phosphite in the course of the reaction, and optimization of the two phosphorus functionalities resulted in the production of versatile and efficient catalysts for this class of hydrogenations: enantioselectivities of up to 98% ee were thus obtained
Chiral phosphine-phosphites provide versatile catalysts for the highlyenantioselectivehydrogenation of alpha-acyloxy alpha, beta-unsaturated phosphonates.
手性膦-亚磷酸酯为α-酰氧基α,β-不饱和膦酸酯的高度对映选择性氢化提供了多种催化剂。
Highly Enantioselective Synthesis of α-Hydroxy Phosphonic Acid Derivatives by Rh-Catalyzed Asymmetric Hydrogenation with Phosphine–Phosphoramidite Ligands
Readily Available Chiral Phosphine−Aminophosphine Ligands for Highly Efficient Rh-Catalyzed Asymmetric Hydrogenation of α-Enol Ester Phosphonates and α-Enamido Phosphonates
[GRAPHICS]A new class of unsymmetrical hybrid phosphine-aminophosphine ligands has been prepared from commercially available, inexpensive (S)-1-phenylethylamine through a concise synthetic procedure. These ligands are not very sensitive to air and moisture, and displayed good enantioselectivities in the Rh-catalyzed asymmetric hydrogenation of various dimethyl alpha-benzoyloxyethenephosphonates bearing beta-aryl, beta-alkyl, and beta-alkoxy substituents and N-benzyloxycarbonyl alpha-enamido phosphonates, in which up to 97% ee was obtained. A side-by-side comparison study disclosed that these new phosphine-aminophosphine ligands showed better enantioselectivity than BoPhoz ligands.