Asymmetric Synthesis of α,α-Disubstituted Amino Acids by Cycloaddition of (<i>E</i>)-Ketonitrones with Vinyl Ethers
作者:Xiaofei Zhang、Pascale Cividino、Jean-François Poisson、Pavlo Shpak-Kraievskyi、Mathieu Y. Laurent、Arnaud Martel、Gilles Dujardin、Sandrine Py
DOI:10.1021/ol500483t
日期:2014.4.4
Original acyclic (E)-α,α-dialkylketonitrones bearing a chiral auxiliary on their nitrogen atom were synthesized and successfully employed for the asymmetricsynthesis of α,α-disubstitutedaminoacids using regio- and stereocontrolled 1,3-dipolar cycloaddition reactions with vinyl ethers. N-Glycosyl chiral auxiliaries were found to provide excellent exo- and π-facial stereocontrol. The obtained enantiopure