Potassium Carbonate → 3-chloro-6-nitro-1-(2-pyrrolidin-1-yl-ethyl)-1H-indazole

Beteiligte Stoffe

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Reaktionsschritte

A mixture of 3-chloro-6-nitro-1H-indazole (2.4 g, 12 mmol) was treated with potassium carbonate (5.0 g, 36 mmol) in DMF (40 mL) for about 30 minutes, after which 1-(2-chloro-ethyl)-pyrrolidine (3.1 g, 18 mmol) was added. The mixture was heated to 50° C. for 6 hours, cooled to room temperature and filtered through a plug of silica gel which was rinsed with triethylamine/ethyl acetate (1/4). The combined filtrate was concentrated under reduced pressure and purified by flash chromatography (silica gel, triethylamine/ethyl acetate 1/30) to provide the title compound (2.3 g, 66%). 1H NMR (300 MHz, DMSO-d6) ppm 1.61 (m, 4H), 2.47 (m, 4H), 2.89 (t, J=6.44, 2H), 4.67 (t, J=6.44, 2H), 7.90 (m, 1H), 8.01 (m, 1H), 8.86 (m, 1H); MS (DCI/NH3) m/z 295 [M+H]+.

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