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The general procedure for the synthesis of 1,6-dibromoisoquinolin-3-amine from 5-bromo-2-cyanophenylacetonitrile was as follows: 4-bromo-2-(cyanomethyl)benzonitrile (75 g, 339 mmol) was dissolved in 2,2-dichloroacetic acid (150 mL, 339 mmol). The reaction mixture was cooled to 0°C in an ice water bath. HBr gas (27.5 g, 339 mmol) was passed into the cooled solution until a yellow precipitate was observed to precipitate and form a yellow slurry. The passage of HBr gas was continued for 5 min. Subsequently, the reaction mixture was slowly warmed up to room temperature over a period of 1 hour. The slurry was again cooled to 0 °C in an ice water bath and ether (200 mL) was added. The mixture was stirred at 5 °C for 20 min. The yellow solid product was collected by filtration to give 1,6-dibromoisoquinolin-3-amine (42 g, 41% yield). lcms (API-ES) m/z: 303 (M + H+).

[1] Tetrahedron Letters, 2007, vol. 48, # 3, p. 487 - 489
[2] Patent: WO2009/11871, 2009, A2. Location in patent: Page/Page column 188; 189
[3] Patent: WO2009/11880, 2009, A2. Location in patent: Page/Page column 159-160
[4] Patent: WO2010/83246, 2010, A1. Location in patent: Page/Page column 54; 55