3-Oxo-azetidine-1-carboxylic acid tert-butyl ester → 3-(3-Oxo-4-pyrimidin-2-yl-piperazin-1-yl)-azetidine-1-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsschritte

A solution of intermediate 3b (120 mg, 0.43 mmol) in TFA (0.75 mL) and CH2Cl2 (3 mL) was stirred at room temperature for 1.5 h. The solution was concentrated. The resulting residue was stirred with N-Boc-azetidin-3-one 1a (81 mg, 0.47 mmol) and Na(OAc)3BH (100, 0.47 mmol) in 1,2-dichloroethane (4 mL) and HOAc (0.2 mL) at room temperature overnight. The reaction was quenched with aq. NaHCO3. The resulting mixture was extracted with CH2Cl2. The organic solution was dried over Na2SO4 and concentrated. Purification by column chromatography (silica gel, 3% MeOH/CH2Cl2) gave intermediate 3c as light yellow solid (15 mg).

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