Cesium carbonate → (S)-5-Oxo-1-(6-trifluoromethyl-pyridin-3-yl)-pyrrolidine-2-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of cesium carbonate (1.539 g; 4.725 mmol), copper bromide (0.032 g; 0.225 mmol) and ethyl-2-oxocyclohexanecarboxylate (0.072; 0.45 mmol) in anhydrous dimethyl sulfoxide (1.25 mL) is degassed with argon and stirred 30 minutes. To this solution is added (S)-5-oxo-pyrrolidine-2-carboxylic acid tert-butyl ester (0.5 g; 2.699 mmol) and 5-bromo-2-trifluoromethylpyridine (0.508 g; 2.25 mmol) in 1 mL anhydrous dimethyl sulfoxide. The mixture is heated in a sealed tube to 60° C. in an oil bath and stirred overnight. The reaction mixture is cooled to room temperature, filtered through Celite® and washed with ethyl acetate. The combined organics are washed with brine, dried over sodium sulfate and concentrated under reduced pressure. ESI m/z 331 [M+H]+

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