Synthesis and characterization of poly(2,6-triptycene)

We report the syntheses of two monomers, 2,6-dibromotriptycene and 2,6-diiodotriptycene, and their applications in the homopolymerization via a nickel(0)-mediated Yamamoto-type polycondensation polymerization, leading to a novel aromatic polymer-poly(2,6-triptycene). This new polymer was characterized by H-1 and C-13 NMR spectroscopy, which exhibited an excellent match with the NMR spectra of the model compound, 2,2'-bitriptycene. In addition, the polymer was found to be highly soluble in common organic solvents, although it does not contain any flexible side chains. This good solubility was attributed to its high content of triptycene units, whose rigid three-dimensional structure was proposed to prevent dense packing of polymer chains. A highly transparent film could be obtained by spin-casting a chloroform solution. This polymer also demonstrated good thermal stability.