1-Hydroxybenzotriazole → 3-[2-(2-Methylsulfanyl-pyrimidine-4-carbonyl)-pyrazolidin-1-yl]-3-oxo-propionic acid ethyl ester

Beteiligte Stoffe

Reaktionsschritte

To a solution of the 3-oxo-3-pyrazolidin-1-yl propionic acid ethyl ester, 11, (8.8 g, 47.7 mmol) in DMF (165 mL) is added 2-methylsulfanyl-pyrimidine-4-carboxylic acid (8.5 g, 50.1 mmol), followed by 1-hydroxybenzotriazole (12.9 g, 95.5 mmol) and then 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (11.0 g, 57.3 mmol). The reaction mixture is stirred at room temperature for 22 hours then poured into aqueous saturated NaHCO3. The aqueous phase is extracted three times with EtOAc and the combined organic phases are dried (MgSO4), filtered and concentrated in vacuo to afford 10.5 g of the desired compound which is used without further purification.

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