Diisopropylethylamine → tert-butyl(2S,3S)-5-(2-methoxy-2-oxoethyl)-2-[(3-phenylpyrrolidin-1-yl)carbonyl]piperidine-3-carboxylate

Beteiligte Stoffe

Reaktionsschritte

To an oven-dried 5 mL conical vial equipped with a magnetic stir bar and under a nitrogen gas atmosphere was placed sequentially: (2S,3S)-3-(tert-butoxycarbonyl)-5-(2-methoxy-2-oxoethyl)piperidine-2-carboxylic acid (50 mg, 0.166 mmol), anhydrous DMF (2 mL), BOP reagent (100 mg, 0.226 mmol), 3-phenyl-pyrrolidine (25 mg, 0.17 mmol), and N,N-diisopropyl ethylamine (0.086 mL, 0.49 mmol). After stirring the reaction mixture overnight, the reaction was quenched with 5% citric acid (1 mL) and the reaction mixture was diluted with ethyl acetate (15 mL) and water (4 mL). The aqueous layer was extracted with ethyl acetate (3×3 mL) and the combined organic phases were washed with saturated sodium bicarbonate (3×5 mL), brine (5 mL), dried (NaSO4), and concentrated in-vacuo to afford 75 mg of crude product that was used directly in the following hydrolysis. LCMS (ESI): 431 (M+H), 375 (M-t-Bu+2H+).

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