Asymmetric Allenylation of Alkynes mediated by Chiral Organoselenated Reagents under Oxidative Conditions
Rongyu Sun1, Emilie Viaud1, Rajesh Nomula1
1Univ. Bordeaux, ISM (CNRS-UMR 5255), 351 cours de la Libération., 33405, Talence Cedex, France.
Abstract:
The reactivity of novel chiral lactamide-substituted diselenide-based reagents under oxidative conditions was exploited to develop a metal-free method for the preparation of enantioenriched allenylamides from simple alkynes in good yields, and with enantiomeric excesses up to 99 %. The key of the success in this method is attributed to the hydrogen-bonded lactamide appendages that ensure configurational stability of chiral vinyl selenoxide intermediates for an optimal enantiotopic β-syn-elimination step.
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