Diisopropylethylamine → 8-Bromo-(1,2,4)triazolo(1,5-a)pyridin-2-amine

Participants

Reaction Conditions

Reaction Steps

To a solution of hydroxylamine hydrochloride (0.10 kg, 1.4 mol, 5.0 equiv) and N,N-diisopropylethylamine (112 g, 0.867 mol, 3.00 eq) in 1:1 methanol/ethanol (1.5 L) was added ethyl [(3-bromopyridin-2-yl)carbamothioyl]carbamate (88 g, 0.29 mmol, 1 equiv) in one portion at room temperature. After 2 h, the reaction mixture was warmed to 60° C. for overnight. The reaction mixture was concentrated in vacuo, and water was added to the resulting residue. The solids were filtered and rinsed sequentially with 4:1 methanol/diethyl ether and diethyl ether to provide product as an off-white solid (25 g, 40%). LCMS (ESI) m/z: 212.8; 1H NMR (400 MHz, DMSO-d6) δ: 8.55 (m 1H), 7.70 (m, 1H), 6.75 (m, 1H), 6.20 (br s, 2H).

Provenance & Evidence