Synthesis of Pyrene Diimide Isomers with Tunable Excimer Emission

The optoelectronic properties of pyrene diimides (PyDIs) are of strategic interest given the successful application of similar rylene diimides as n-type organic semiconductors in a variety of organic electronics. We present an improved synthesis for 1,5,6,10-pyrene diimide and the first report of its isomer, 1,8,9,10-pyrene diimide. We demonstrate the effect of imide placement on the core structure, optical properties, and electron affinities. Notably, we have discovered that both isomers exhibit tunable aggregation-induced excimer emission and that 1,8,9,10-PyDI exhibits anti-Kasha emission.