Poly[4,6-bis(bis(4-methoxyphenyl)aminium)-1,2-phenylenevinylene]: A high-spin and durable polyradical

A purely organic and high-spin polyradical molecule was synthesized, along the non-Kekulé and non-disjoint design of the π-conjugated poly(1,2-phenylenevinylene) backbone pendantly 4,6-substituted with the robust arylaminium radicals. 4,6-Bis(bis(4-methoxyphenyl)amino)-2-bromostyrene was synthesized and polymerized with a Pd-phosphine catalyst to afford the head-to-tail linked polyradical precursor. Oxidation of the polymer with SbCl₅ gave the aminium polyradical with a half-life of >10 days at room temperature. A high-spin ground state with an average S = 5/2 for this polyradical was proved by magnetic susceptibility and ESR.