Hydrogen Bromide → 5-Bromo-1-(2-(pyrrolidin-1-yl)ethyl)-1H-indazole

Participants

Reaction Conditions

Reaction Steps

A solution of NaNO2 (0.20 g, 2.8 mmol) in H2O (5 mL) was cooled in a wet ice bath and treated with a solution of 1-(2-(pyrrolidin-1-yl)ethyl)-1H-indazol-5-amine (0.65 g, 2.8 mmol) in 48% aqueous HBr (2 mL). The resulting mixture was added to a pre-heated solution of CuBr (0.49 g, 3.4 mmol) in 48% aqueous HBr (2 mL) at 100° C. After stirring at 100° C. for 15 min, the dark mixture was allowed to cool. The solids were isolated by filtration, washed with 1N NaOH, and dried under vacuum. Purification by flash column chromatography (silica gel, CH2Cl2/MeOH, 95:5 to 90:10 gave the title compound (0.21 g, 25%) as a brown solid: ESI MS m/z 294 [M+H]+.

Provenance & Evidence