Synthesis of novel multifunctional carbazole-based molecules and their thermal, electrochemical and optical properties

• Published in: Beilstein journal of organic chemistry 2020-05, Vol.16 (1), p.1066-1074
• Main Authors: Altinolcek, Nuray, Battal, Ahmet, Tavasli, Mustafa, Peveler, William J, Yu, Holly A, Skabara, Peter J
• Format: Article
• Language: English
• Subjects: Carbazole; Chemistry; Chromatography; Dichloromethane; Differential scanning calorimetry; electrochemistry; Electrodes; Energy; fluorescence; formyl group; Full Research Paper; Magnetic resonance spectroscopy; Mass spectroscopy; NMR; Nuclear magnetic resonance; Optical properties; Organic light emitting diodes; Oxidation; Phase transitions; Potassium; Sensors; solvatochromism; Spectrum analysis
• ISSN: 1860-5397; 2195-951X; 1860-5397
• DOI: 10.3762/bjoc.16.93

Two novel carbazole-based compounds and were synthesised as potential candidates for application in organic electronics. The materials were fully characterised by NMR spectroscopy, mass spectrometry, FTIR, thermogravimetric analysis, differential scanning calorimetry, cyclic voltammetry, and absorption and emission spectroscopy. Compounds and , both of which were amorphous solids, were stable up to 291 °C and 307 °C, respectively. Compounds and show three distinctive absorption bands: high and mid energy bands due to locally excited (LE) transitions and low energy bands due to intramolecular charge transfer (ICT) transitions. In dichloromethane solutions compounds and gave emission maxima at 561 nm and 482 nm with quantum efficiencies of 5.4% and 97.4% ± 10%, respectively. At positive potential, compounds and gave two different oxidation peaks, respectively: quasi-reversible at 0.55 V and 0.71 V, and reversible at 0.84 V and 0.99 V. At negative potentials, compounds and only exhibited an irreversible reduction peak at -1.86 V and -1.93 V, respectively.