Carbazolo[2,1‐a]carbazole Diimide: A Building Block for Organic Electronic Materials

Abstract

AbstractA new class of carbazolo[2,1‐a]carbazole diimide compounds (CBZCBZ‐DI, 3) are designed and synthesized. The synthesis, X‐ray crystal structure, absorption spectra, and electrochemical properties of 3 as well as the charge transport properties are investigated. Theoretical calculation is also carried out based on the X‐ray crystal structure of 3 a to understand the relationship between the structure and the charge transport properties. Single‐crystal X‐ray analysis revealed that the molecules of 3 a adopt a slipped face‐to‐face π‐stacking mode with a large intermolecular π‐overlap and an interplanar distance of 3.4 Å. Crystalline transistors of 3 a display high hole mobility of 0.5 cm2 V−1 s−1, which is among the highest reported mobility values for carbazole‐based N‐heteroacenes. Two useful brominated derivatives (4, 5) are also prepared for synthesizing more new π‐functional materials.