The synthesis and spectroscopic characterization of poly(p-phenylene ethynylene) with 3-connected BODIPY end groups

A novel 3-connected BODIPY end-capped poly(p-phenylene ethynylene) and a matching model compound were synthesized by palladium-catalyzed cross-coupling reaction. The structures were confirmed using 1H NMR, UV–vis spectrophotometry and fluorescence spectroscopy. Both the polymer and the model compound showed absorption and emission bands characteristic for the BODIPY chromophore and the p-phenylene ethynylene linker. However, while upon excitation of the p-phenylene ethynylene linker energy transfer occurs for nearly 100% in the model compound, it is only a minor decay channel of the singlet excited state of the p-phenylene ethynylene linker in the polymer.