Synthesis of D-π-A high-emissive 6-arylalkynyl-1,8-naphthalimides for application in Organic Field-Effect Transistors and optical waveguides

Donor-π-Acceptor (D-π-A) compounds based on a 1,8-naphthalimide core branched with different alkynyl donor groups have been synthesized, characterized and tested in Organic Field-Effect Transistors (OFETs) and as optical waveguides. The aim was to design materials with promising applications in new organic optoelectronic devices, namely Organic Field-Effect Optical Waveguides (OFEW). Computational studies showed that these compounds possess suitable electronic properties to behave as efficient semiconductors in OFETs and as optical waveguides. The former application is evidenced by the optimal energetic values of the frontier molecular orbitals and intramolecular reorganization energies, whereas the latter application is possible due to the high Stoke shifts and strong tendency to self-assemble. This last feature has been corroborated by NMR aggregation studies in solution. The experimental results indicate that the three studied semiconductors are active in OFETs, with electron field effect mobilities close to 10⁻² cm²V⁻¹s⁻¹ for compound 1c. Furthermore, compound 1b also shows excellent behavior as an optical waveguide, thus making it a good candidate to be applied in OFEWs.