Tert-Butyl nitrite → 5-bromo-1H-indazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

tert-Butyl nitrite (8.34 g, 0.081 mol) was added dropwise, over 30 minutes, to a suspension of 4-bromo-2-methylacetanilide (12.3 g) in toluene (300 ml) at 65° C. and the mixture was stirred at 65° C. for 45 minutes and then at 90° C. for 3 hours. The mixture was cooled to room temperature and the solvent was removed in vacuo. The residue was purified by flash column chromatography on silica gel eluting with 2:1 diethyl ether:hexane to give 5-bromoindazole (4.12 g), as a sand-coloured solid.

Herkunft & Nachweise