Reports: GB3
46789-GB3 Scope and Mechanism of Aromatic Perfluoroalkylation by Iron Reagents
Perfluoroalkyl groups, especially as trifluoromethyl-substituted aromatic substructures, are common functionalities in man-made biologically-active compounds. We have previously reported an arene-limiting perfluoroalkylation procedure using anaerobic and anhydrous conditions. We have found conditions that give equally good yields when the reaction is performed in air and with wet solvent. The scope of the reaction was expanded to include branched perfluoroalkyl chains. This optimized procedure was used to prepare perfluoroalkyl analogs and derivatives of common analgesics. It was observed that electron-rich arenes were perfluoroalkylated faster than electron-deficient arenes. Furthermore, no kinetic isotope effect was observed for the perfluoroalkylation reaction. We have proposed a mechanism based on these findings, and further investigations into this mechanism are underway.
