Water → Methyl 6-(trifluoromethyl)-1H-indazole-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of (2-acetylamino-4-trifluoromethylphenyl)-acetic acid methyl ester (16 g, 0.058 mol) in acetic acid (50 mL) was added dropwise t-butyl nitrite (90%) (7.35 g, 0.063 mol) over a period of 20 min. at 90-95° C. The mixture was then stirred for 0.5 h at 95° C., poured into cold water and stirred for 1 h. The precipitates were collected by filtration and washed with water. The crude material was dissolved in ethyl acetate and dried over sodium sulfate. The solvent was removed in vacuo. This material (13.4 g, 95%) was used without further purification in the next step. A small sample was crystallized from ethyl acetate to yield a white solid, mp 240-242° C. 1H NMR (DMSO-d-6) 8.25 (d, J=8.5 Hz, 1H), 8.04 (s, 1H), 7.58 (d, J=8.5 Hz, 1H), 3.95 (s, 3H). MS (FAB) m/z: 245.1 (M++1).

Provenance & Evidence