Trifluoroacetic acid → HCID 23138722, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of the mixture as above in dimethyl sulfoxide (100 ml), was added potassium thioacetate (12.3 g). The resulting mixture was stirred at 80° C. for 15 hours, cooled to room temperature, and diluted with water to stop the reaction. The products were extracted with ethyl acetate. The organic layer was washed with a saturated aqueous sodium chloride solution. The organic layer was dried over anhydrous aqueous sodium chloride, and solvents were evaporated in vacuo. The residue was purified by chromatography on silica gel using a mixture of hexane, ethyl acetate and dichloromethane (2:1:1) as the eluent to afford an approximately 7:6:1 mixture of (E)-4-(acetylsulfanyl)-3-{[1-(ethoxycarbonylmethyl)-1H-pyrazol-4-yl]methylidene}-1-(triphenylmethyl)piperidine, its (Z)-isomer and 5-{(acetylsulfanyl)[1-(ethoxycarbonylmethyl)-1H-pyrazol-4-yl]methyl}-1-(triphenylmethyl)-1,2,3,6-tetrahydropyridine (5.52 g). To a solution of the above mixture in dichloromethane (300 ml) was added trifluoroacetic acid (1.9 ml). The resulting mixture was stirred at room temperature for 15 minutes. The solvent was evaporated in vacuo, and the residue was purified by chromatography on silica gel using a mixture of dichloromethane and methanol (10:1) as the eluent to afford the title compound as a yellow amorphous solid (1.75 g, overall yield: 33%).

Provenance & Evidence