Metal-free synthesis of alkynyl imines using an oxophosphonium-mediated approach at ambient temperatures

A metal-free approach was developed for the mild synthesis of N-aryl α-alkynyl imines from corresponding amide precursors for the first time. The electronic effects of substrates and the reaction mechanisms were investigated and discussed. This newly developed oxophosphonium-triggered one-pot multiple-step method presents the advantages of mild conditions, ease of operation and satisfactory efficiency.