Synthesis of an Ionic Polyacetylene Derivative via the Non-catalyst Polymerization of 2-Ethynylpyridine Using 4-(Bromomethyl)-7-methoxycoumarin

Abstract

A new ionic polyacetylene with coumarin moieties was synthesized via the non-catalyst polymerization of 2-ethynylpyridine using 4-bromomethyl-7-methoxycoumarin in high yield. The polymerization proceeded well in homogeneous manner to give 75% of yield without any additional catalyst or initiator. The polymer structure was identified by such various instrumental methods as NMR, IR, and UV-visible spectroscopies to have a conjugated backbone with the designed coumarin groups. The photoluminescence peak was observed at 512 nm corresponding to a photon energy of 2.42 eV. The cyclovoltamograms of polymer exhibited the electrochemically stable window at the −1.8 ∼ 1.50 V region. Oxidation and reduction were started at 0.58 and −0.8 V and had stable electrochemical property up to 30 cycles.

Keywords:

• polyacetylene
• non-catalyst
• ethynylpyridine
• 4-bromomethyl-7-methoxycoumarin
• cyclovoltammogram

Acknowledgments

This work was supported by the National Research Foundation of Korea (NRF) grant funded from the Ministry of Education, Science and Technology (MEST) of Korea (No. 2011-0028320, No. 2012-001846). The authors thank Mrs S. E. Chae of Korea Basic Science Institute-Taegu Branch for the measurement of 500-MHz FT-NMR spectra of polymers.