3-Oxo-azetidine-1-carboxylic acid tert-butyl ester → HCID 66823705, compound

Participants

Reaction Steps

A solution of intermediate 2a (610 mg, 2.56 mmol) in TFA (2 mL) and CH2Cl2 (8 mL) was stirred at room temperature for 2 h. The solution was concentrated. The resulting residue was stirred with N-Boc-azetidin-3-one 1a (526 mg, 3.07 mmol) and Na(OAc)3BH (651, 3.07 mmol) in 1,2-dichloroethane (8 mL) and HOAc (0.8 mL) at room temperature overnight. Additional 1a (175 mg, 1.02 mmol) and Na(OAc)3BH (217 mg, 1.02 mmol) was added. The reaction was stirred for another 5 h before it 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, 6% MeOH/CH2Cl2) gave intermediate 2b as light yellow solid (268 mg).

Provenance & Evidence