Unexpected Direct Synthesis of N-Vinyl Amides through Vinyl Azide-Enolate [3+2] Cycloaddition
Hans Choi1, Harry J Shirley1, Paul A Hume1
1School of Chemical Sciences, University of Auckland, 23 Symonds St, Auckland, 1010, New Zealand.
Abstract:
The unexpected synthesis of industrially important N-vinyl amides directly from aldehydes and α,β-unsaturated N-vinyl amides from esters is reported. This reaction probably proceeds through an initial [3+2] azide-enolate cycloaddition involving a vinyl azide generated in situ. A survey of the reaction scope and preliminary mechanistic findings supported by quantum computational analysis are reported, with implications for the future development of atom-efficient amide synthesis. Intriguingly, this study suggests that (cautious) reevaluation of azidoethene as a synthetic reagent may be warranted.
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