1,6‐Dinitroperylene Bisimide Dyes: Synthesis,Characterization and Photophysical Properties

1,6‐ and 1,7‐regioisomers of dinitro‐substituted perylene bisimides ( 1a — 1b and 2a — 2b ) were synthesized under mild condition in high yields. The 1,6‐ and 1,7‐regioisomers were successfully isolated from the regioisomeric mixture using conventional methods of separation and subsequently characterized by 500 MHz ¹H NMR spectroscopy. This is the first time when 1,6‐dinitroperylene bisimides ( 1a — 1b ) are obtained in pure form. Furthermore, the photophysical and electrochemical properties of 1 and 2 were found to be almost the same. The nitro functionalities provide stability of n‐type charge carriers by lowering the LUMO to resist ambient oxidation, which may offer potential applications in air‐stable n‐type organic semiconductors.