Preparation of Polyaminopyridines Using a CuI/l-Proline-Catalyzed C-N Polycoupling Reaction

Polyaminopyridines (PAPy) were chemically prepared from amino-bromopyridines by a CuI/l-proline-catalyzed C-N polycondensation reaction. The formation of the polymer was confirmed by GPC, XRD, XRF, FTIR, UV-vis (λ(max) = 400 nm), (1)H and (13)C NMR. The number-average molecular weights (M(n)) were estimated by end-group analysis using X-ray fluorescence (up to 6000 Da). TGA analysis of PAPy with higher M(n) showed greater thermal stability up to 170 (o)C. Viscosity measurements of polymer in formic acid at 30 (o)C indicated a polyelectrolyte nature of PAPy solutions. Furthermore, the amorphicity of the material was observed by X-ray diffraction analysis.