F. Hapiot et al., ASYMMETRIC CATALYTIC-HYDROGENATION OF ALPHA-KETOESTERS USING NEW CHIRAL RU(II)(AMPP) COMPLEXES, Tetrahedron : asymmetry, 6(1), 1995, pp. 11-14
Chiral bidentate amino(amido)phosphinephosphinite ligands (AMPP) have
been used to synthesise new ruthenium bismethylallyl Ru(AMPP)(CH2C(CH3
)CH2)(2) and biscarboxylate Ru(AMPP)(OCOR)(2) (R = CH3 or CF3) complex
es. These complexes act as efficient catalyst precursors for the homog
eneous asymmetric hydrogenation of alpha-ketoesters with enantiomeric
excesses up to 79%.