Ammonium Chloride → 7-Methoxy-4-propionyl-2-trifluoromethyl-pyrazolo[1,5-a]pyridine

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Reaction Steps

Vinyl magnesium chloride (1.32 mol/L tetrahydrofuran solution, 22.7 mL) was added dropwise to a solution of the compound of Example 115 (6.09 g) in tetrahydrofuran (250 mL) at −78° C. in a stream of argon gas. The mixture was allowed to gradually warm to room temperature. A saturated aqueous ammonium chloride solution was then added and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. The solvent was evaporated to give a pale yellow oil. This product was dissolved in chloroform (500 mL). To the solution, activated manganese dioxide (75%, 100 g) was added and the mixture was stirred at room temperature for 8 hours. Subsequently, additional activated manganese dioxide (75%, 50 g) was added and the mixture was stirred at room temperature overnight. Manganese dioxide was removed by filtration through Celite (thoroughly washed with ethyl acetate) and the solvent was evaporated to afford the title compound as a yellow powder (5.39 g).

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