Ethyl orthoformate → 5-Bromo-8-methoxy-[1,2,4]triazolo[4,3-A]pyrazine

Participants

Reaction Conditions

Reaction Steps

A 100 mL round bottom flask was charged with 5-bromo-3-hydrazinyl-2-methoxypyrazine (0.5 g crude, ˜1.9 mmol) and triethyl orthoformate (5 mL). The resulting mixture was heated at 130° C. overnight. TLC indicated a complete conversion. Work-up: the reaction mixture was concentrated. The residue was purified by flash column chromatography on silica gel with a 1:50 methanol/dichloromethane, to afford 0.28 g (66% for 2 steps) of the product as a pale yellow solid. 1H NMR (300 MHz, CDCl3) δ: 8.93 (s, 1H), 7.47 (s, 1H), 4.18 (s, 3H). MS m/z: 229 (M+H+).

Provenance & Evidence