Pyrazole → 5-Bromo-3-nitro-2-(1H-pyrazol-1-yl)pyridine

Participants

Reaction Conditions

Reaction Steps

To a mixture of 5-bromo-2-chloro-3-nitropyridine (10 g, 42 mmol) in 1,4-dioxane (100 ml) was added pyrazole (5.8 g, 85 mmol). The resulting mixture was stirred at 120° C. for 26.5 h., and then evaporated after cooling to r.t. The crude material was purified by flash chromatography (0 to 5% EtOAc/Hexanes) to give the desired product 5-Bromo-3-nitro-2-pyrazol-1-yl-pyridine. 1H NMR: (CD3OD) δ 8.77 (s, 1H), 8.56 (s, 1H), 8.45 (s, 1H), 7.73 (s, 1H), 6.57 (s, 1H); LC/MS: (ES+) m/z (M+H)+=269, 271, HPLC Rt=1.223.

Provenance & Evidence