Palladium‐Catalyzed Asymmetric Hydrogenation of α‐Acyloxy‐1‐arylethanones

Abstract

Aus erster Hand: Die erste palladiumkatalysierte asymmetrische Hydrierung von α‐Acyloxyketonen (1) ergibt effizient und hoch enantioselektiv die Hydrierungsprodukte 2, die als Zwischenstufen in der Herstellung vieler Wirkstoffkandidaten nützlich sein könnten. TFE=2,2,2‐Trifluorethanol.

Versatile Iridicycle Catalysts for Highly Efficient and Chemoselective Transfer Hydrogenation of Carbonyl Compounds in Water

“…Selective reduction of analogues of 3 m by TH is difficult, because the acyl group is prone to migration by hydrolysis. [17] Indeed, there are only a few literature reports describing the TH of this class of substrates; however, the catalyst loadings are high and the yields are relatively low due to the aforementioned problem. [18] To the best of our knowledge, this is the first time that a homogeneous catalyst has been reported for the TH of a-piperidyl and a-semialdehyde ketones.…”

“…Still further, the catalytic system was successfully applied to α‐acyloxy, α‐morpholino and α‐semialdehyde ketones ( 3 m – 3 p ; Table 3, entries 13–16), with the α‐functional groups tolerated and high yields obtained for all of the desired products. Selective reduction of analogues of 3 m by TH is difficult, because the acyl group is prone to migration by hydrolysis 17. Indeed, there are only a few literature reports describing the TH of this class of substrates; however, the catalyst loadings are high and the yields are relatively low due to the aforementioned problem 18.…”