C-F Bond Activation of Highly Fluorinated Molecules at Rhodium: From Model Reactions to Catalysis

Rhodium complexes are excellent tools for the activation of aromatic and olefinic carbon-fluorine bonds. C-F bond cleavage reactions are key steps for the derivatization of highly fluorinated compounds via stoichiometric or catalytic reaction pathways. The reaction routes involve hydrodefluorinations, but also the selective introduction of functional groups at distinctive positions, to provide access to new fluorinated building blocks. One can identify two general types of rhodium precursors that can induce the C-F activation step. Cyclopentadienyl compounds have been applied for thermal and photochemical C-F bond cleavage reactions of aromatics in solution, but oxidative addition steps have also been investigated in matrix isolation studies at low temperature. Square-planar hydrido, silyl, and boryl complexes are often involved in unique stoichiometric and catalytic processes for the derivatization of aromatics and olefins.