ABSTRACT
The structure of the ruthenium(H)-BINAP catalyst prepared from [(COD)RuCl2]n and BINAP in the presence of triethylamine has been characterized by proton, carbon, phosphorus and 2D NMR spectroscopy. Treatment of this material with a strong acid in deuterated methylene chloride or methylene chloride/methanol provides a new species. Treatment of this second species with hydrogen produces ruthenium hydrides observed in the proton NMR spectrum at -9.7 to-11.7 ppm. Hydrides are not observed in the absence of a strong acid. The hydrides produced are capable of reducing methyl acetoacetate to methyl 3-hydroxybutyrate with high enantiomeric excess.
