Chiral-at-metal iridium complex for efficient enantioselective transfer hydrogenation of ketones.

نویسندگان

  • Cheng Tian
  • Lei Gong
  • Eric Meggers
چکیده

A bis-cyclometalated iridium(III) complex with metal-centered chirality catalyzes the enantioselective transfer hydrogenation of ketones with high enantioselectivities at low catalyst loadings down to 0.002 mol%. Importantly, the rate of catalysis and enantioselectivity are markedly improved in the presence of a pyrazole co-ligand. The reaction is proposed to proceed via an iridium-hydride intermediate exploiting metal-ligand cooperativity (bifunctional catalysis).

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عنوان ژورنال:
  • Chemical communications

دوره 52 22  شماره 

صفحات  -

تاریخ انتشار 2016