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Enantioselective reduction of 3-substituted quinolines has been achieved using a cyclopentadiene-based chiral Brønsted acid as catalyst and Hantzsch ester as hydrogen donor, affording the corresponding tetrahydroquinolines in good enantioselectivities. [ABSTRACT FROM AUTHOR]

A ruthenium pincer catalyst has been shown to be highly effective for the hydrogenation of a wide range of α-keto esters, affording either diols or hydroxy esters depending on the choice of reaction conditions. Strong base, high temperature, and pressure favor the formation of diols whilst the opposite is true for the hydroxy esters. [ABSTRACT FROM AUTHOR]

The combination of a chiral phosphoric acid with an irid-ium complex affords a catalyst that allows for highly enantioselec-tive hydrogenation of imines. Mechanistic studies suggest that the hydrogenation proceeds through a ternary transition state at the hydride-transfer step, in which the organocatalyst interacts with both the hydride donor and acceptor. [ABSTRACT FROM AUTHOR]

A robust cyclometalated iridium catalyst has been developed for highly effective hydrogenation of imines. With very low catalyst loading (down to 0.005%), good to excellent yields have been achieved for a range of substrates in a short reaction time under mild conditions, providing an easy, efficient protocol for making amines [ABSTRACT FROM AUTHOR]