Diisopropylethylamine → 6-Bromo-[1,2,4]triazolo[1,5-a]pyridin-2-amine

Participants

Reaction Conditions

Reaction Steps

A mixture of hydroxylamine hydrochloride (40.0 g, 575 mmol) and N-ethyldiisopropylamine (44.6 g, 60.3 ml, 345 mmol) in ethanol (734 ml) was stirred for a few minutes at 25° C., then the mixture was added to 1-ethoxycarbonyl-3-(5-bromo-pyridin-2-yl)-thiourea (35 g, 115 mmol) and the resulting mixture was refluxed for 1 day. The solvent was evaporated under reduced pressure and the white solid was treated with 400 ml water. The suspension was stirred for 1 hour, the solid was filtered off, washed with water 3 times and dried under reduced pressure, affording 6-bromo-[1,2,4]triazolo[1,5-a]pyridin-2-ylamine (21 g, 85%) as white solid. Mp.: 185° C. MS: m/z=213.0/215.1 (M+H+).

Provenance & Evidence