Tuning the LUMO Levels of Z-Shaped Perylene Diimide via Stepwise Cyanation.

The central dogma in constructing organic electron acceptors is to attach electron-withdrawing groups to polycyclic aromatic hydrocarbons. Yet, the full potentials of many organic acceptors were never realized due to synthetic obstacles. By combining the Wittig-Knoevenagel benzannulation, the Pd(0)-catalyzed cyanation, and nucleophilic addition/oxidation cyanation, six polynitrile Z-shaped perylene diimide were synthesized.

New synthetic routes to Z-shape functionalized perylenes.

Z-shape (1,2,7,8-tetrasubstituted) perylene derivatives are novel chromophores with great potential in various applications. Yet, the synthetic entry into this class of molecules is hitherto quite limited. In this communication, the synthesis of a series of Z-shape perylene derivatives via a double Wittig-Knoevenagel benzannulation protocol is reported.