747385-19-9Relevant academic research and scientific papers
Bifunctional Br?nsted Base Catalyzes Direct Asymmetric Aldol Reaction of α-Keto Amides
Echave, Haizea,López, Rosa,Palomo, Claudio
, p. 3364 - 3368 (2016/03/22)
The first enantioselective direct cross-aldol reaction of α-keto amides with aldehydes, mediated by a bifunctional ureidopeptide-based Br?nsted base catalyst, is described. The appropriate combination of a tertiary amine base and an aminal, and urea hydro
Formamides derived from N-methyl amino acids serve as new chiral organocatalysts in the enantioselective reduction of aromatic ketimines with trichlorosilane
Malkov, Andrei V.,Ston?ius, Sigitas,MacDougall, Kenneth N.,Mariani, Andrea,McGeoch, Grant D.,Ko?ovsky, Pavel
, p. 264 - 284 (2007/10/03)
Asymmetric reduction of N-aryl ketimines 1a-k, 43, and 45 with trichlorosilane can be catalyzed by new N-methyl l-amino acid-derived Lewis-basic organocatalysts, such as the valine-derived bisamide 3d (10 mol%), in toluene at room temperature with high enantioselectivity (≤92% ee). The structure-reactivity investigation shows that the product configuration is controlled by the nature of the side chain of the catalyst scaffold (e.g., i-Pr vs Me, as in 3d and 6e), so that catalysts of the same absolute configuration may induce the formation of the opposite enantiomers of the product. Arene-arene interactions between the catalyst and the incoming imine appear to be the prerequisite for asymmetric induction. This metal-free, organocatalytic protocol is competitive with the traditional, metal-catalyzed methodology.
