Pd-Catalyzed Direct C–H Alkenylation and Allylation of Azine <i>N</i>‑Oxides

A Pd-catalyzed direct C₂-alkenylation of azine <i>N</i>-oxides with allyl acetate is disclosed. The products are formed through an allylation/isomerization cascade process. The use of a tri-<i>tert</i>-butylphosphonium salt as the ligand precursor and KF is mandatory for optimal yields. When cinnamyl acetate is used, the same catalytic system promotes C₂-cinnamylation of the azine <i>N</i>-oxide without subsequent isomerization. A mechanism is proposed on the basis of experimental studies and DFT calculations