Synthesis
The general procedure for the synthesis of 2,8-dibromodibenzothiophene from dibenzothiophene was as follows: dibenzothiophene (15.1552 g, 82.25 mmol) was dissolved in chloroform (150 mL) and bromine (13.0 mL, 253.72 mmol) was slowly added dropwise at 0 °C in an ice bath. After the dropwise addition, the reaction mixture was kept at 0 °C for 2 hours. Subsequently, the reaction system was slowly warmed to room temperature and stirring was continued for 3 days. After completion of the reaction, excess methanol was added to the mixture and stirred for 30 min to precipitate the product. The white solid product was collected by vacuum filtration and washed with excess methanol to finally obtain 2,8-dibromodibenzothiophene (22.87 g, 66.86 mmol, 81% yield).
References
[1] Chemistry - An Asian Journal, 2017, vol. 12, # 5, p. 552 - 560
[2] Patent: WO2017/13420, 2017, A1. Location in patent: Page/Page column 11
[3] Journal of Materials Chemistry, 2003, vol. 13, # 6, p. 1351 - 1355
[4] Journal of the American Chemical Society, 2010, vol. 132, # 12, p. 4466 - 4476
[5] New Journal of Chemistry, 2015, vol. 39, # 3, p. 2096 - 2105
