Combining Bidentate Lewis Acid Catalysis and Photochemistry: Formal Insertion of o-Xylene into an Enamine Double Bond.

A bidentate Lewis acid catalyzed domino inverse-electron-demand Diels-Alder reaction combined with a photoinduced ring opening formally inserts o-xylene moieties into enamine double bonds. After reduction, phenethylamines were obtained in good yields. The scope of the reaction was determined by variation of all three starting compounds: phthalazines, aldehydes, and amines.