Ethyl trifluoroacetate → HCID 22185798, compound

Participants

Reaction Conditions

Reaction Steps

synthesis. Step a. The preparation of 4-(4-trifluoromethylphenyl)acetophenone was carried out as follows. To the mixture of 4-bromobenzotrifluoride (1.0 g, 4.4 mmol) and 4-acetylphenylboronic acid (0.739 g, 4.4 mmol), Pd(OAc)2 (1.97 mg), K2CO3 (1.54 g), Bu4NBr (1.43 g) and H2O (7 mL) were added, The mixture was stirred under argon for 30 min, warmed to 70° C., and kept stirring for 1 hr. The solution was cooled to room temperature, diluted with water, extracted with ethyl acetate. The intermediate was purified by Silica gel chromatography with yield of 86%. Step b. To a cooled solution of ethyl trifluoroacetate (1.0 g, 7.04 mmol) in CH2Cl2, NaH (338 mg, 14.1 mmol) was added, stirred for 15 min., and then a solution of 4-(4-trifluoromethylphenyl)acetophenone (1.86 g, 7.04 mmol) in CH2Cl2 was added. The mixture was stirred at room temperature for 6 hrs, Silica gel chromatography afforded the 4,4,4-trifluoro-1-(4-(4-trifluoromethylphenyl)phenyl)butane-1,3-dione (2.1 g, 83% yield). Step c. (4-Sulfamoylphenyl) hydrazine hydrochloride (200 mg, 0.89 mmol) was added to a stirred solution of the above dione (320 mg, 0.89 mmol) in 20 mL of ethyl acetate, The mixture was headed to reflux and stirred for 24 hr. After cooling to room temperature, the reaction mixture was concentrated in vacuo. The residue was dissolved in ethyl acetate, washed with water and brine. The product was purified by chromatography to give the title compound (290 mg, 71% yield).

Provenance & Evidence