Visible Light‐Induced Synthetic Approach for Selenylative Spirocyclization of N‐Aryl Alkynamides with Molecular Oxygen as Oxidant

A visible light‐induced (blue LED) radical cascade has been devised to effect selenylative spirocyclization of N‐aryl alkynamides at room temperature under oxygen atmosphere and without the aid of external photocatalyst. The protocol is operationally simple, scalable, and offers clean synthesis of 3‐selenospiro[4,5]trienones in high yields (up to 92%). A novel spiro‐ring‐opening strategy has also been accomplished to access fully substituted acryl amides. magnified image