Potassium Carbonate → 5-nitro-1-(pyridin-2-ylmethyl)-1H-indazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 5-nitroindazole (40.75 g, 250 mmol), picolyl chloride hydrochloride (45.1 g, 275 mmol) and potassium carbonate (72.4 g, 525 mmol) in DMF (400 ml) was heated at 75° C. for 3 hours. Additional picolyl chloride hydrochloride (4.1 g, 25 mmol) and potassium carbonate (3.45 g, 25 mmol) were added and the mixture was heated at 75° C. for 2 additional hours. After cooling, the mixture was diluted with water (800 ml). The precipitate was filtered, washed with water and dried. The resulting solid was purified by chromatography on silica gel (eluant: 50% ethyl acetate in petroleum ether) to give 5-nitro-1-(pyridin-2-ylmethyl)-1H-indazole as a solid (34.5 g, 55%); NMR Spectrum (CDCl3) 5.77 (s, 2H), 7.03 (d, 1H), 7.23 (m, 1H), 7.55 (d, 1H), 7.63 (m, 1H), 8.27-8.23 (m, 2H), 8.58 (m, 1H), 8.74 (d, 1H); Mass spectrum MH+ 255.

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