Synthesis of benzocarbazole isomer as a model study to determine the extend of byproduct formation of dibenzo[b,g]carbazole in the synthesis of dibenzocarbazole

• Main Author: Foo, KaiYu.
• Other Authors: Andrew Clive Grimsdale
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/15299
• Institution: Nanyang Technological University

Development and applications of carbon nanotube has sparked a worldwide research into improving the properties of carbon nanotube (CNT) by functionalization. Dibenzocarbazole monomer was synthesized for the investigation of its polymer wrapping properties and binding strength to single wall carbon nanotube (SWNT). However, the synthesis methodologies of Suzuki coupling and ring closure reaction generated a byproduct of dibenzo[b,g]carbazole. This project uses starting material of 1-bromo-4-chloro-2-nitrobenzene and naphthalene boronic acid to go through a similar reaction methodology of Suzuki coupling and Cadogan ring closure reaction to yield benzocarbozole isomer to investigate and quantify the amount of by product of benzo[a]carbazole generated as a model study to determine the extend of byproduct formation in the synthesis of dibenzocarbazole. Suzuki coupling of 1-bromo-4-chloro-2-nitrobenzene and 1-naphthalene boronic acid was carried out, the product was put through column chromatography to remove impurities and single out the desired product. The reaction succeeded in the production of 1-(4-chloro-2-nitrophenyl)naphthalene, however the yield was very low suggesting possible contamination of the reactants. Cadogan ring closure reaction was not carried out for this route of the synthesis. Suzuki coupling of 1-bromo-4-chloro-2-nitrobenzene and 2-naphthalene boronic acid also succeeded in producing the desired monomer but at a higher conversion yield of approximately 60%. Recrystallization was done for the targeted monomer and ring closure reaction was carried out for this route of the reaction. Cadogan ring closing reaction is still undergoing, result of the reaction will be reflected in the presentation.