Efficient synthesis of N-alkylated α,β-unsaturated ketonitrones via Cu-catalyzed rearrangement.

N-Alkylated unsaturated ketonitrones were efficiently synthesized from propargyloxyamines using Cu catalysts. Mechanistic studies suggest that the rearrangement reaction proceeds via Cu-catalyzed intramolecular hydroamination, followed by thermally induced electrocyclic ring opening.