902772-13-8

The general procedure for the synthesis of 5-bromo-1H-indole-2-carboxamide from 5-bromo-1H-indole-2-carbonitrile was as follows: 5-bromo-1H-indole-2-carboxamide (0.68 mg, 2.84 mmol) was suspended in toluene (20 mL). Phosphoryl chloride (1.326 mL, 14.22 mmol) was added slowly dropwise via syringe under stirring. The reaction mixture was heated to reflux and maintained for 1.5 hours. Upon completion of the reaction, the mixture was poured into saturated sodium bicarbonate solution and quenched. The aqueous phase was extracted twice with dichloromethane (50 mL x 2). The organic phases were combined, washed with brine (20 mL), dried over anhydrous magnesium sulfate and concentrated under reduced pressure to give the crude product. The crude product was purified by silica gel column chromatography (using a Biotage 25 g silica gel column eluting with a 0-5% ethyl acetate/dichloromethane gradient) to afford 5-bromo-1H-indole-2-carbonitrile (0.408 g, 1.85 mmol, 65% yield) as a tan solid. The mass spectrum (ESI, negative ion mode) showed m/z 219/221.

[1] Patent: WO2006/77367, 2006, A1. Location in patent: Page/Page column 120
[2] Patent: WO2014/164749, 2014, A1. Location in patent: Page/Page column 312; 313