5-Bromo-2,1,3-benzoxadiazole

synthetischeTriphenylphosphine (1.1 mmol) was dissolved in dry toluene (3 mL) and stirred at 110°C under argon atmosphere; then 6-bromobenzo[c][1,2,5]oxadiazole 1-oxide (1 mmol) in toluene (0.5 mL) was added dropwise over 1 hour and the resulting mixture was stirred for 3 hours. After completion, the solvent was evaporated in vacuo, and the crude was purified through flash column chromatography (cyclohexane - diethyl ether 98:2) to afford 5-Bromobenzo[c][1,2,5]oxadiazole which is a pale pink solid.