138604-91-8Relevant academic research and scientific papers
Optically active aromatic and heteroaromatic α-amino acids by a one-pot catalytic enantioselective addition of aromatic and heteroaromatic C-H bonds to α-imino esters
Saaby, Steen,Bayon, Pau,Aburel, Pompiliu S.,Jorgensen, Karl Anker
, p. 4352 - 4361 (2007/10/03)
The development of a practical one-pot catalytic enantioselective procedure for the synthesis of non-natural aromatic and heteroaromatic α-amino acids is reported. Starting from readily available starting materials and application of a chiral BINAP-Cu(I) catalyst, the optically active products are formed with readily removable N-protecting groups. The scope of the reaction is demonstrated by the addition of substituted furans, thiophenes, pyrroles, and aromatic compounds to N-alkoxy-carbonyl-α-imino esters in good yields and with enantioselectivities up to 96% ee for the furans, 93% ee for the thiophenes, and 98% for the aromatic compounds. The protecting groups are readily removed, and various transformations of the aromatic and heteroaromatic a-amino acids are demonstrated. The coordination of the N-alkoxycarbonyl α-imino ester to the chiral BINAP-Cu(I) complex and the enantioselectivity of the catalyst is discussed on the basis of the DFT calculations and X-ray crystallographic data.
Enantioselective reduction of C=O and C=N compounds with NADH model N,N,1,2,4-pentamethyl-1,4-dihydronicotinamide
Versleijen,Sanders-Hovens,Vanhommerig,Vekemans,Meijer
, p. 7793 - 7802 (2007/10/02)
The scope and mechanism of enantioselective hydride transfer from NADH model 4 to prochiral C=O and C=N compounds were investigated. Efficient chirality transfer from 4 to α-keto esters and α-methoxycarbonylimino esters was achieved. The resemblance in reactivity and stereochemistry of the prochiral C=O and C=N-CO2Me functionalities in the hydride transfer reaction is attributed to the intervention of a similar Mg(ClO4)2-mediated ternary complex.
NADH model mediated reduction of C=N substrates: Enantioselective synthesis of D- and L-phenylglycinates
Vekemans,Versleijen,Buck
, p. 949 - 952 (2007/10/02)
Hydride transfer from N,N,1,2,4-pentamethyl-1,4-dihydronicotinamide, 1, to methyl 2-methoxycarbonylimino-phenylacetate, 3, was accomplished in an optical yield ≥95%.
