Naphthalene diimides prepared by straightforward method and its characterization for organic electronics

Mateusz Korzec; Sonia Kotowicz; Katarzyna Łaba; Mieczysław Łapkowski; Jan Grzegorz Małecki; Karolina Smolarek; Sebastian Maćkowski; Ewa Schab-Balcerzak

Index: 10.1002/ejoc.201701741

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Abstract

A new approach in the synthesis of acetylene core substituted naphthalene diimides in polar solvent using PdCl2, Et3N and powder electrolytic copper was developed. This simplified approach allows for high‐throughput synthesis where the reaction products can be easily separated. The DFT studies revealed that electronic structures of these compounds are mainly determined by central naphthalene diimide and acetylene derivatives parts. The obtained thermally stable and soluble compounds undergo reversible reduction with electron affinity from 4.18 to 4.28 eV. They emitted green light with photoluminescence quantum yield of about 6% in chloroform and from 3‐12% as thin films. The compounds were applied as emitting layers for both non‐doped and doped single layer OLEDs fabricated by solution processing. Under applied external voltage they feature orange or red light electroluminescence.