Hydrochloric Acid → 1-[N-(2,6-Dibromo-4-fluoro-phenyl)-carbamimidoyl]-1H-pyrazole-4-carboxylic acid ethyl ester

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Reaction Conditions

Reaction Steps

A mixture of 2,6-dibromo-4-fluoro-phenyl-cyanamide (0.167 g, 0.570 mmol), ethyl pyrazole-4-carboxylate (80.0 mg, 0.570 mmol), 4M HCl in dioxane (0.156 mL, 0.630 mmol), and 1,4 dioxane (2 mL) was heated to reflux for 2 h, during which time a precipitate formed. The mixture was allowed to cool to 23° C. Et2O (10 mL) was added to the mixture. The resulting precipitate was collected by filtration, washed with Et2O, and dried to yield the titled compound (0.134 g, 50%) as the HCl salt. MS (ESI/CI): mass calcd. for C13H11Br2FN4O2, 431.9; m/z found, 432.9 [M+H]+. 1H NMR (400 MHz, DMSO-d6): 8.20 (s, 1H), 7.43 (s, 1H), 6.82 (d, J=7.9 Hz, 2H), 3.56 (q, J=7.1 Hz, 2H), 2.85 (s, 3H), 0.57 (t, J=7.1 Hz, 3H).

Provenance & Evidence