11,12-Dihydroindolo[2,3-a]carbazole

Flash Point：269.9±13.9 °C

11,12-Dihydroindolo[2,3-a]carbazole is an isomer of indole[3,2-b]carbazole. 11,12-Dihydroindolo[2,3-a]carbazole derivatives have good planarity, high thermal stability, and excellent photophysical properties. As an optoelectronic material, it is often used to synthesize TADF-OLED body and emission layer materials and as a pharmaceutical intermediate to synthesize anticancer drugs[1-3]. Chemical sensors based on indole[2,3-a]carbazole can be used to detect Cu²⁺ and Fe³⁺ in environmental and biological systems simultaneously[4]. Compared to other metal ions, the sensor has specificity and high sensitivity for the detection of Cu²⁺ and Fe³⁺ ions. For Cu²⁺ and Fe³⁺ ions, detection limits are as low as 2.93×10 -7 M and 4.10×10 -7 M.

1,2-cyclohexanedione (1 g, 8.93 mmol) and phenylhydrazine hydrochloride (3.86 g, 26.78 mmol) were added to the reactor. Nitrogen is flushed into the flask, followed by 20 mL of acetic acid. After stirring and refluxing for 24 hours, the mixture is cooled to room temperature. The reaction mixture is slowly poured into ice water and stirred to precipitate a large amount of yellow solids. It is then filtered, washed with pure water, and dried. After purification, 11,12-Dihydroindolo[2,3-a]carbazole was obtained. Yield=95.6%

11,12-Dihydroindolo[2,3-a]carbazole could used as a donor unit. The electron-rich carbazole and indole units are contained in the plane donor, which helps to increase the electron-donating ability and hole-transporting ability.

[1] Tian J, et al. Synthesis and thermal, electrochemical, photophysical properties of novel symmetric/asymmetric indolo[2,3-a]carbazole derivatives bearing different aryl substituents. Tetrahedron, 2016; 73: 230-238.
[2] Zenkov R, et al. Indolo[2,3- a ]carbazoles: diversity, biological properties, application in antitumor therapy. Chemistry of Heterocyclic Compounds, 2020; 56: 644–658.
[3] Yang S, et al. Synthesis and characterization of novel butterfly-shaped aryl-substituted indolo[2,3-a]carbazole derivatives. Tetrahedron Letters, 2015; 56: 2223-2227.
[4] Chen ;Z, et al. A simple indolo[2,3-a]carbazole based colorimetric chemosensor for simultaneous detection of Cu2+ and Fe3+ ions. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2020; 234: 118236.