Enhanced functionality for donor-acceptor oligothiophenes by means of inclusion of BODIPY: Synthesis, electrochemistry, photophysics, and model chemistry

We have synthesized several new push-pull oligothiophenes based on the boron dipyrromethene (BODIPY) moiety as the electron acceptor and the more well-known oligothiophenes substituted with N,N-dialkylamino functions to enhance their electron-donor ability. A complete characterization of the electronic properties has been carried out; it consists of their photophysical, electrochemical, and vibrational properties. The compounds have been studied after chemical treatment with acids and after oxidation. In this regard, they can be termed as NIR dyes and amphoteric redox electroactive molecules. We have described the presence of dual fluorescence in these molecules and fluorescence quenching either by energy transfer or, in the push-pull molecules, by electron exchange. The combination of electrochemical and proton reversibility along with the interesting optical properties of the new species offer an interesting platform for sensor and material applications.