Annulation Cascade of Aryl Alkynes Induced by Alumina‐Mediated CF Bond Activation

Alumina‐mediated CF activation (AmCFA) is an established method to generate incipient phenyl cation (IPC) through polarization of C(aryl)F bonds. Herein, it is reported that AmCFA can be used to induce intramolecular arylation of aryl alkynes containing one, two, and three triple bonds. During the reaction, a single formally eliminated hydrogen fluoride (HF) leads to the formation of two, three, and four CC bonds, respectively. Thus, the transformation gives rapid access to π‐extension and serves as an interesting example of solid‐state rational domino annulation enabling the bottom‐up construction of nanographenes.