Sulfuric Acid → HCID 117903099, compound

Participants

Reaction Steps

A mixture of 1,2,4,6-tetramethyl-1H,2H,3H-pyrazolo[4,3-c]pyridin-3-one (0.33 g, 1.7 mmol), NBS (0.34 g, 1.9 mmol) and conc. H2SO4 (8 ml) is stirred at RT for 18 h. The mixture is poured onto ice-water. The water phase is made basic with an aqueous solution of sodium hydroxide (1 mol/l) and extracted with DCM. The combined organic layers are dried over MgSO4 and concentrated in vacuo. 7-bromo-1,2,4,6-tetramethyl-1H,2H,3H-pyrazolo[4,3-c]pyridin-3-one is used without further purification. Yield: 0.37 g (80%). HPLC-MS: M+H=270/272; tR=0.77 min (METHOD—1).

Provenance & Evidence