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Published on: January 15, 2018
Intramolecular 6-exo-dig Post-Ugi Cyclization of N-Substituted 2-Alkynamides: Direct Access to Functionalized
Harikesh Kumar, Gurudayal Prajapati, Atul Dubey
1Academy of Scientific and Innovative Research, Ghaziabad 201002, India.
Abstract:
We herein report a chemo- and regioselective 6-exo-dig catalytic cyclization of Ugi adducts N-substituted 2-alkynamides to access functionalized morpholinone glycoconjugates in the presence of triphenylphosphine. This array allows an interesting multicomponent access to a library of functionalized morpholinone glycoconjugates under mild reaction conditions with regeneration of catalyst triphenylphosphine, supported by 31P nuclear magnetic resonance studies. Density functional theory shows the 6-exo-dig oxocyclization pathway is preferred, which supports our experimental observation.
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