Ethyl formate → HCID 178506113, compound

First, 3.18 g (79.4 mmol) of a 60% sodium hydride suspension in mineral oil was added in portions to a solution of 9.96 g (52.9 mmol) of 4-trifluoromethylacetophenone and 12.6 mL (158.76 mmol) of ethyl formate in 75 mL of anhydrous tetrahydrofuran at 0° C. The mixture was allowed to reach ambient temperature, at which an exothermic reaction occurred, which subsided in 5 min. After 1 h, the mixture was concentrated and the residue was triturated with diethyl ether to provide a tan solid in two crops. The solid was suspended in 1N hydrochloric acid and the resulting bright yellow solid was filtered and washed with water. The solid was dissolved in 150 mL of methanol and stirred at room temperature with 4.7 mL (96.9 mmol) of hydrazine hydrate for 3 h. Solvent was evaporated and the resulting solid was suspended in water, stirring for 18 h. The solid was filtered, washed with water, and dried under vacuum to provide 8.9 g (80%) of 3-[4-(trifluoromethyl)phenyl]-1H-pyrazole as a yellow solid. 1H-NMR (DMSO-d6): δ 13.05 (br s, 1H), 7.99 (d, J=8 Hz, 2H), 7.8 (br s, 1H), 7.71 (d, J=8 Hz, 2H), 6.81 (s, 1H); ES-LCMS m/z 213 (M+H).

1. customto reach ambient temperature, at which
2. customan exothermic reaction
3. waitAfter 1 h
4. concentrationthe mixture was concentrated
5. customthe residue was triturated with diethyl ether
6. customto provide a tan solid in two crops
7. filtrationthe resulting bright yellow solid was filtered
8. washwashed with water
9. dissolutionThe solid was dissolved in 150 mL of methanol
10. customSolvent was evaporated
11. filtrationThe solid was filtered
12. washwashed with water
13. customdried under vacuum

ORD record

ord-ffc54b8a23544ca78efa848f2e4f3bbc

Source dataset

uspto-grants-2007_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07288541B2