2-Oxobutanoic Acid → HCID 23114371, compound

Participants

Reaction Steps

To a solution of 2-oxobutanoic acid (259 mg, 2.54 mmol) in THF (5 mL) was added dropwise with ice-cooling oxalyl chloride (0.33 mL, 3.80 mmol) and added DMF (three drops), and the mixture was stirred for 30 minutes. The reaction solution was warmed to room temperature and stirred at the same temperature for 1 hour, and then the solvent was distilled off under reduced pressure. The residue was dissolved in dichloromethane (5 mL) and the product was added dropwise with ice-cooling to a solution of 3-(4-isopropylphenyl)-4,6,7-trimethyl-2,3-dihydro-1-benzofuran-5-amine (500 mg, 1.69 mmol) obtained in Reference Example 30 and triethylamine (0.24 mL, 1.69 mmol) in THF (5 mL), and the resulting mixture was stirred for 30 minutes. After the reaction solution was warmed to room temperature, water was added to the reaction solution and the product was extracted with ethyl acetate. The organic layer was washed with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and then concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (hexane:ethyl acetate=2:1) to obtain 363 mg (yield: 57%) of the title compound. Yield: 57%. Melting point: 97-98° C. (ethyl acetate-hexane).

Provenance & Evidence