Nitrilooxonium tetrafluoroborate → 5-Bromo-3-fluoropyridine-2-carboxamide

Participants

Reaction Steps

To a solution of 3-amino-5-bromopyridine-2-carboxamide (40.0 g, 185.2 mmol) in CH2Cl2 was added nitrosonium tetrafluoroborate (22.71 g, 191.4 mmol). The reaction was stirred at room temperature for 4.5 hours, then concentrated in vacuo and azeotroped with toluene. The residue was suspended in toluene (1100 mL) and heated to 100° C. for 2 hours. The reaction was concentrated in vacuo, and the residue suspended in CH2Cl2. The solid was collected to provide 5-bromo-3-fluoropyridine-2-carboxamide that gave proton NMR spectra consistent with theory and a mass ion (ES+) of 219.1 for M+H+(79Br).

Provenance & Evidence