1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → 4-[4-(4-Ethyl-5-fluoro-2-methoxyphenoxy)-3-fluorobenzoyl]piperazine-2,6-dione

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Reaction Steps

N,N-Diisopropylethylamine (0.29 mL, 1.7 mmol), piperazine-2,6-dione hydrochloride (88 mg, 0.58 mmol), EDCI (112 mg, 0.58 mmol) and HOBt (79 mg, 0.58 mmol) were successively added to a solution of 4-(4-ethyl-5-fluoro-2-methoxyphenoxy)-3-fluorobenzoic acid (which may be prepared in accordance with the experimental described in Example 4, step 4; 150 mg, 0.48 mmol) in dichloromethane (1.6 mL). The reaction mixture was stirred at room temperature overnight then diluted by addition of dichloromethane (20 mL) and a saturated solution of ammonium chloride (20 mL). After separation, the aqueous layer was extracted with dichloromethane (2×20 mL). The combined organic phases were washed with a saturated solution of sodium hydrogen carbonate (20 mL), dried over sodium sulfate, filtered and concentrated under vacuum. The residue was purified by chromatography on silica gel, using dichloromethane/methanol (95:5 to 90:10) as eluent. The title product was obtained as a beige solid (130 mg, 66%).

Provenance & Evidence