Synthesis of Polytrifluorostyrene Derivatives via Iridium-Catalyzed C—H Activation/Borylation and Subsequent Transformation

Novel polytrifluorostyrene (PTFS) derivatives with pendant pinacolboronate groups (PTFS-Bpin) were successfully prepared via aromatic C—H activation/borylation reactions in the presence of chloro(1,5-cyclooctadiene)iridium(I) dimer(［IrCl(COD)］2) and 4,4′-di-tert-butyl bipyridine (dtbpy). The contents of pinacolboronate groups incorporated into the PTFS were effectively controlled by adjusting the mole ratios of boron reagents related to polymer repeating units. The Suzuki-Miyaura coupling reactions between PTFS-Bpin and aryl bromide containing carbonyl group or sulfonyl group were conducted. The structures and properties of the resulted polymers were analyzed by NMR (1H-NMR, 11B-NMR and 13C-NMR), Gel Permeation Chromatography (GPC), Differential Scanning Calorimetry (DSC), and Thermal Gravimetric analysis (TG), etc. Results showed that the side chain modified PTFS possessed good solubility and thermal stability. The existence of boronate group in PTFS made it possible to introduce other functional side chains.