Arene fluorination and trifluoromethylation enabled by tetravalent group 10 metals ('formally' NiIV, PdIV, PtIV)

Organofluorine compounds, mainly those containing F itself or trifluoromethyls (−CF 3 ) in arenes, are ubiquitous in pharma/agrochemical industries and material science, making them essential to the well-being of mankind. The metal-mediated aryl−R f bond formations (R f = F, CF 3 ) are commonly hampered by multiple factors (low nucleophilicity of the F − anion, strong M−CF 3 bonds, difficult transmetallation, moisture sensitivity, etc.). Accordingly, the finding of synthetic schemes to build aryl−R f bonds constitutes a major challenge in modern coordination/organometallic chemistry. This review seeks to critically summarize the most appealing approaches to aryl−F/CF 3 couplings taking place from structurally characterized M IV R f species (M = Ni, Pd, Pt; R f = F, CF 3 ). The concept of inverted ligand field (ILF) often displayed by some of the ‘formally’ M IV R f species compiled herein, together with spectroscopic and reactivity insights supporting the ILF electronic structure picture, is also introduced and briefly discussed.