One-Pot Methylenation-Cyclization Employing Two Molecules of CO₂ with Arylamines and Enaminones

One-pot methylenation-cyclization employing two molecules of CO₂ with enaminones and primary aromatic amines was discussed for the first time to access cyclized products. This 1,5,7-triazabicyclo[4.4.0]dec-5-ene and ZnCl₂-catalyzed procedure was characterized by the selective conversion of two molecules of CO₂ into methylene groups in a multicomponent cyclization reaction. According to the computational study and control experiments, the reaction might proceed through the generation of bis(silyl)acetal and condensation of arylamine and aza-Diels-Alder processes. Moreover, the resulting products will probably be potential organic building blocks with adjustable photophysical properties.