Functionalization of poly(p-phenylenevinylene) polymers with pendant nitroxide groups

In the search for novel organic ferromagnetic polymers we devised synthetic routes to poly-p-phenylenevinylenes with nitroxide functional groups. Reaction of the Grignard reagent derived from the ROC6H4(CH2)nBr precursor (R=CH3, n=4; R=n-C6H13, n=6) with CO2 gave an acid which was chloromethylated and subsequently coupled to the paramagnetic TEMPOL group. The paramagnetic monomers could be readily converted to the diamagnetic hydroxylamine salts to permit full NMR characterization. The paramagnetic monomers were polymerized via the KOtBu route to the corresponding PPV.