Ethyl bromopyruvate → Ethyl cis(+/-)-2-(4-{[(benzyloxy)carbonyl]amino}-3-methoxypiperidin-1-yl)-1,3-oxazole-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

Ethyl bromopyruvate (2.93 g, 15 mmol) and sodium bicarbonate (2.10 g, 25 mmol) were added to a solution of cis(±)-benzyl (1-carbamoyl-3-methoxypiperidin-4-yl)carbamate obtained in Example (103b) (1.4 g, 4.56 mmol) in THF (30 mL), and the mixture was stirred at 70° C. for three hours. The insoluble matter was filtered off, followed by dilution with ethyl acetate. This was washed with water and brine, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (elution solvent: ethyl acetate/hexane=1/4, 1/2, 1/1, 2/1, 4/1) to obtain 1.46 g of the title compound as a colorless solid (79%).

Provenance & Evidence