Carbazoledioxazines having long alkyl groups. 2 . Synthesis of carbazoledioxazines with angular type structure

Carbazoledioxazines with an angular type structure (5,15‐dialkyl‐7,17‐dialkyloxy‐9,19‐dichloro‐5,15‐dihydrodiindolo[2,3‐ c :2′,3′‐ n ]triphenodioxazines) were selectively synthesized by electrochemical oxidative ring closure of precursors (2,5‐bis(9‐alkyl‐2‐alkyloxy‐3‐carbazolylamino)‐3,6‐dichloro‐1,4‐benzoquinones). The structure was confirmed by 1 H‐nmr and other instrumental analyses. Their thermal properties and solubilities were investigated and were compared with those of carbazoledioxazines with a linear type structure.