Triethylamine → HCID 17956316, compound

Participants

Reaction Conditions

Reaction Steps

To a 0° C. solution of 1-(4-fluorophenyl)-2-[2-(methylsulfanyl)pyrimidin-4-yl]ethanone oxime (4.0 g, 14 mmol) in ethylene glycol dimethyl ether (40 mL) was added trifluoroacetic anhydride (3.0 g, 14 mmol) dropwise. The reaction was allowed to warm to 20° C., then re-cooled to 0° C. Triethylamine (2.9 g, 29 mmol) was added dropwise so that the internal reaction temperature did not exceed 10° C. The reaction was allowed to warm to room temperature and was stirred for 2 hours. Iron (II) chloride (18 mg, 0.14 mmol) was added and the mixture heated to 80° C. for 2 hours. An additional portion of iron (II) chloride (18 mg, 0.14 mmol) was added and the mixture heated at 80° C. for 2 hours. An additional portion of iron (II) chloride (18 mg, 0.14 mmol) was added and the mixture heated at 80° C. for 4 hours. The reaction was allowed to cool to room temperature and stirred overnight. The mixture was partitioned between ethyl acetate and water. The aqueous phase was extracted with ethyl acetate (2×20 mL) and the organic layers combined. The organic phase was washed with brine, dried over magnesium sulfate, filtered and concentrated. The residue was purified by silica chromatography eluting with 1% acetone in dichloromethane to yield 2.54 g (68%) of 2-(4fluorophenyl)-7-(methylsulfanyl)-pyrazolo[1,5-c]pyrimidine. 1H NMR (CDCl3): δ 8.04 (dd, 2H),7.80 (d, 1H), 7.20 (m, 3H), 6.79 (s, 1H), 2.76 (s, 3H). MS m/z 260 (M+1).

Provenance & Evidence