Ligand containing chiral phosphine

Ruthenium and Rhodium Hydrides Containing Chiral Phosphine or Chiral Sulfoxide Ligands, and Catalytic Asymmetric Hydrogenation... 

EDITOR S NOTE In 1982, J Halpem (University of Chicago) reported that rhodium complexes containing chiral phosphine ligands catalyze the hydrogenation of olefinic substrates such as alpha-aminoacrylic acid derivatives, producing chiral products with very high optical yields. 

Parrinello G, Stille JK (1987) Asymmetric hydroformylation catalyzed by homogeneous and polymer-supported platinum complexes containing chiral phosphine ligands. J Am Chem Soc 109 7122-7127... 

Malacea R. Daran J-C, Duckett SB, Dunne JP, Manoury E, Poli R, Withwood AC (2006) Parahydrogen studies of H2 addition to hfl) complexes containing chiral phosphine-thioether ligands implications for catalysis. Dalton Trans 3350-3359... 

In 2004, excellent enantioselectivities of up to 98% ee were obtained by Morimoto et al. by using a phosphine-sulfonamide-containing 1,1 -binaphthyl-based ligand in the enantioselective copper-catalysed conjugate addition of ZnEt2 to several benzylideneacetones (Scheme 2.27). Similar levels of enan-tioselectivity (up to 97% ee) combined with excellent yields (up to 90%) were obtained by Leighton et al. for the copper-catalysed enantioselective addition of various alkylzincs to cyclic enones performed in the presence of other chiral phosphine-sulfonamide ligands (Scheme 2.27). ... 

Togni and co-workers have used the convergent methodology to link phosphine-containing chiral ferrocene ligands on the cyclophosphazene core to obtain dendrimeric structures of the type 37 (Fig. 21) (201). The reaction with the cyclophosphazene end occurs by the replacement of the P-Cl bond and by the formation of the P-0 bond. The dendrimers contain twelve and sixteen ferrocene moieties respectively. The phosphine units present can coordinate to Rh(I) to afford metallic dendrimers, which have been shown to be excellent catalysts for the enantioselective hydrogenation of dimethyl itaconate. The product... 

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