Uses
4-Bromophthalic anhydride is a white or grayish-white crystalline solid at room temperature and pressure. It can be used as an intermediate in organic and biochemical synthesis, and for the derivatization of drug molecules and bioactive molecules. In addition, 4-Bromophthalic anhydride can also be used in the synthesis of dye intermediates and plant growth regulators.
Chemical Properties
off-white to white powder
Synthesis
To a suspension of phthalic anhydride (1) (22 g, 148.5 mmol, 1.0 eq.) in water (150 mL) was slowly added sodium hydroxide (12 g, 300.0 mmol, 2.0 eq.) and pure bromine (8.5 mL, 165.9 mmol, 1.1 eq.). The reaction mixture was stirred at 90 °C for 12 hours. Upon completion of the reaction, the mixture was cooled to 0 °C and filtered to collect a pale yellow solid. After washing the solid with cold water (50 mL), it was dissolved in sulfur dioxide (60 mL) and the mixture was heated to reflux for 5 hours. The reaction mixture was concentrated and dichloromethane (200 mL) was added to the residue and stirred at room temperature for 2 hours. After filtration, the filtrate was concentrated to give 5-bromoisobenzofuran-1,3-dione (2) (20 g, 71% yield) as a yellow solid.1H NMR (400 MHz, CDCl3) δ 8.16-8.17 (m, 1H), 8.06-8.07 (m, 1H), 7.89-7.90 (m, 1H).
References
[1] Patent: CN105399712, 2016, A. Location in patent: Paragraph 0025
[2] Patent: US2010/204214, 2010, A1. Location in patent: Page/Page column 109
[3] Journal of Medicinal Chemistry, 2017, vol. 60, # 3, p. 1142 - 1150
[4] Patent: WO2018/95260, 2018, A1. Location in patent: Paragraph 058; 060; 0116
[5] Journal of Medicinal Chemistry, 1993, vol. 36, # 22, p. 3417 - 3423
