Ammonium Chloride → Methyl 5-((3R*,4S*)-4-{[(benzyloxy)carbonyl]amino}-3-methoxypiperidin-1-yl)-3-(1-hydroxyethyl)thiophene-2-carboxylate

Participants

Reaction Steps

A solution of methylmagnesium bromide (0.97 mol/L) in THF (1.59 mL, 1.54 mmol) was added to a solution of methyl cis(±)-5-(4-{[(benzyloxy)carbonyl]amino}-3-methoxypiperidin-1-yl)-3-formylthiophene-2-carboxylate obtained in Example (246c) (333 mg, 0.77 mmol) in THF (8 mL) at 0° C., and the mixture was stirred at room temperature for five hours. Saturated ammonium chloride solution was added to the reaction solution, and the reaction solution was extracted with ethyl acetate. The combined organic layers were washed with brine and then dried over anhydrous magnesium sulfate. Following filtration, the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (elution solvent: hexane/ethyl acetate=1/1) to obtain 223 mg of the title compound as a pale yellow solid (65%).

Provenance & Evidence