Palladium-catalyzed cycloaromatization polymerization of enediynes.

Bergman cyclization has shown great promise in constructing conjugated polymers. However, the application of this reaction in polymer science is still limited due to the harsh reaction condition and ill-defined structure of the achieved polymers. To this end, the cycloaromatization polymerization of enediynes catalyzed by a series of transition metal catalysts is investigated in this work, by taking advantage of the coordination chemistry of the enediyne with the transition metal complexes. According to the nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), ultraviolet-visble (UV-Vis) spectroscopies and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, the cycloaromatization polymerization of enediynes proceeds under milder conditions and in a more controlled manner in the presence of palladium(II) complexes, giving structurally regulated conjugated polymers in high yields. [ABSTRACT FROM AUTHOR]