Synthesis of new poly(arylamine)s (aryl = oligo-p-phenyl or pyridyl) by organometallic polycondensation and chemical properties of the polymers

A series of poly(arylamine)s formulated as [-(Ar)(m)NR-](n) (Ar = p-phenylene or pyridine-2,5-diyl; m = 2-4; R = H or alkyl) were prepared. Ni- or Pd-promoted dehalogenative polycondensation of the corresponding BOC- (tert-butoxycarbonyl-) substituted dibromo monomers afforded poly(oligo-p-phenyleneamine) s, [-(p-C6H4)(m)N(BOC)-](n) (m = 2-4). Deprotection of the BOC group of the polymer at 200 degrees C gave [-(p-C6H4)mNH-](n) (m = 2-4). The polymer behaved as an intermediate polymer between poly(aniline) PAn and poly(p-phenylene) PPP. For example, [-(p-C6H4)(2)NH-](n), P(DPA), showed two oxidation peaks at around 0.3 and 0.65 V vs Ag+/Ag with equal intensity in its CV (cyclic voltammetry) chart, similar to PAn; in contrast, the CV chart of[-(p-C6H4)(4)NH-](n) exhibited a main oxidation peak at 0.60 V vs Ag+/Ag, similar to PPP. ESR data of iodine-doped polymers supported the formation of radical species in oxidation of the polymer. The polymers were photoluminescent and gave quantum yields of 12-46%. Polymers with the pyridine unit formed metal complexes with MX2 (M = Cu, Ni, Co), and CD (circular dichroism) spectra of the metal complexes of the pyridine polymer having chiral side chains suggested formation of a helical structure by the metal complexation.