CuII-Catalyzed Coupling with Two Ynone Units by Selective Triple and Sigma C–C and C–H Bond Cleavages

We report a new copper-catalyzed [2 + 2 + 1] annulation process through the selective cleavage of sigma and triple C–C and C–H bonds using two ynone units. This new methodology involves breaking multiple chemical bonds in a single operation, including C≡C, C–C, C–H, and N–O. These high-value adducts lead to a diverse collection of synthetically challenging trisubstituted indolizines by the simultaneous engagement of different bond-breaking events and show excellent fluorescence in green aqueous solutions.