Synthesis
Step 1: 3-chloro-2-nitroaniline (5.0 g, 29 mmol), zinc powder (18.9 g, 290 mmol) and ammonium chloride (31.0 g, 579 mmol) were stirred in 100 mL of a 1:1 ethanol-water mixture for 18 hours at room temperature. After completion of the reaction, the reaction mixture was filtered and the filtrate was concentrated to give a brown solid. The solid was transferred to a partition funnel and partitioned with dichloromethane and water. The organic layer was separated, the organic extracts were combined, dried with anhydrous magnesium sulfate, filtered and the solvent was removed in vacuum to give 3-chlorobenzene-1,2-diamine (4.00 g, 97% yield) as a brown solid.
References
[1] Journal of Medicinal Chemistry, 2010, vol. 53, # 3, p. 1357 - 1369
[2] Patent: US2010/120778, 2010, A1. Location in patent: Page/Page column 29
[3] Patent: WO2008/118468, 2008, A1. Location in patent: Page/Page column 132
[4] Patent: WO2009/134750, 2009, A1. Location in patent: Page/Page column 72
[5] ACS Medicinal Chemistry Letters, 2017, vol. 8, # 5, p. 543 - 548
