Cyano-capped molecules: versatile organic materials

Abstract

Conjugated small molecules bearing the cyano group were reviewed. These organic compounds are extensively used as active layers of solar cells and light-emitting diodes as well as materials with high second- and third-order nonlinearities. Typical organic light conversion agents are also based on CN-capped π-conjugated scaffolds that, in addition, are also increasingly popular for building various organic sensors and probes. More recently, cyanoarenes and dicyanopyrazines were identified as efficient photoredox catalysts. Fundamental structure–property relationships of CN-capped molecules used across the aforementioned areas were elucidated and discussed. The cyano group possessing electron-withdrawing character and linear arrangement is capable of significantly altering electronic and optical properties, and supramolecular arrangement. Hence, extensive property tuning/regulation through the CN group has been demonstrated.