Platinum-Catalyzed Asymmetric Hydrogenation: Spectroscopic Evidence for an O-H-O Hydrogen-Bond Interaction between Substrate and Modifier


  • We thank Dr. Tamas Mallat (ETH Zurich) for valuable discussion.


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The mighty cinchonidine: A diastereomeric surface complex in the asymmetric hydrogenation of ketopantolactone on chirally modified Pt is monitored by in situ ATR-IR spectroscopy, in combination with modulation excitation spectroscopy and phase-sensitive detection. Cinchonidine bound to the surface with its quinoline ring is shown to induce the chiral environment through a C9[BOND]O⋅⋅⋅H⋅⋅⋅O[DOUBLE BOND]C interaction (see scheme).