Sodium Hydroxide → 2,2,2-Trichloroethyl 3-tert-butyl-1-(4-cyanophenyl)-1H-pyrazol-5-ylcarbamate

Beteiligte Stoffe

Reaktionsschritte

4-(5-Amino-3-tert-butyl-1H-pyrazol-1-yl)benzonitrile (11.8 g, 49.1 mmol) was added to 70 mL of 3 N NaOH and 100 mL of ethyl acetate and the reaction mixture was cooled in an ice-bath. 2,2,2-Trichloroethyl carbonochloridate (9.34 mL, 68.7 mmol) was slowly added and the reaction was warmed to ambient temperature with stirring overnight. The ethyl acetate layer was washed with 3 N HCl and brine, and the organic layer was dried over MgSO4, filtered and concentrated to an oil. Hexane was added to this oil and the mixture was stirred rapidly until a solid formed. The solids were triturated in hexanes, filtered, and dissolved in minimal warm ethyl acetate. Hexanes were added to the ethyl acetate solution until a slight cloudiness was observed. Material was allowed to crystallize and the solids were collected by filtration to yield 6.3 g of the desired product as a white solid, MS M+1 (416).

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