Nickel-catalyzed C-F activations enabled chemo-divergent CC formation with alkynes by chelation assistance. The judicious choice of the alkynes electronic properties allowed the selective synthesis of double-insertion aromatic homologation or alkyne mono-annulation products by C-F/C-H activation. Based on the unambiguous crystallographic characterization of an unprecedented 9-membered nickelocyclic intermediate and extensive DFT studies, a plausible mechanistic rationale was established for the selective C-F activation and the chemodivergent catalysis.

Cross-coupling transformations are a powerful tool in organic synthesis. It is known that this kind of transformations undergoes 2-electron redox processes and, for this reason, silver has been nearly forgotten as catalyst for cross-couplings since silver is mainly considered as a 1-electron redox metal. Herein, we disclose effective Ag(I)-catalyzed cross-coupling transformations using bidentate aminoquinoline as a directing group towards different nucleophiles to form CC , C-N and CO bonds. DFT calculations indicate the feasible oxidative addition of L 1-I substrate via Ag(I)/Ag(III) catalytic cycle. Furthermore, ion spectroscopy experiments suggest a highly reactive aryl-Ag(III) that in absence of nucleophiles reacts to form an intermolecular cyclic product [5d-Ag(I)-CH 3 CN], which in solution forms 5a. This work proves that silver can undergo 2-electron redox processes in cross-coupling reactions like Pd and Cu.

A secondary phosphine oxide (SPO)-nickel catalyst allowed the activation of otherwise inert C–F bonds of unactivated arenes in terms of challenging couplings with primary and secondary alkyl Grignard reagents. The C–F activation is characterized by mild reaction conditions and high levels of branched selectivity. Electron-rich and electron-deficient arenes were suitable electrophiles for this transformation. In addition, this strategy also proved suitable to heterocycles and for the activation of C–O bonds under slightly modified conditions.

A Ni‐catalyzed Csp2−OMe ortho‐functionalization methodology to form chemoselectively alkyne monoannulation or aromatic homologation products is reported as a novel protocol towards the valorisation of substrates containing Csp2−OMe units. Double activation of Csp2−OMe and Csp2−F bonds is also demonstrated. Further use of aromatic homologation products towards the synthesis of nanographene‐like compounds is described.

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