770718-92-8

General procedure for the synthesis of 3-hydroxy-5-bromobenzonitrile from 3-bromo-5-methoxybenzonitrile: Anhydrous colistin (100 mL) was added to a dry flask, followed by 3-bromo-5-methoxybenzonitrile (10.4 g, 49 mmol) and lithium iodide (LiI, 19.6 g, 3 equiv). The reaction mixture was heated to 150 °C and kept overnight under nitrogen protection. After completion of the reaction, the mixture was cooled to room temperature and slowly poured into ice-cold 1 M hydrochloric acid (HCl) solution. The aqueous phase was extracted using a 1:1 mixture of ethyl acetate (EtOAc)/hexane and the organic phase was washed with water and dried with anhydrous magnesium sulfate (MgSO4). Finally, the target product 3-hydroxy-5-bromobenzonitrile (8.7 g, 89% yield) was obtained by vacuum concentration.

[1] Patent: US2005/239881, 2005, A1. Location in patent: Page/Page column 47-48
[2] Patent: US2008/20981, 2008, A1. Location in patent: Page/Page column 19
[3] Patent: US2008/45511, 2008, A1. Location in patent: Page/Page column 21
[4] Patent: US2008/293664, 2008, A1. Location in patent: Page/Page column 16
[5] Patent: US2008/249151, 2008, A1. Location in patent: Page/Page column 21