反应详情

A 25 mL round-bottomed flask was charged with (2R,3R)-2-(((9H-fluoren-9-yl)methoxy)carbonylamino)-3-hydroxybutanoic acid (184 mg, 0.54 mmol), 3-fluoroazetidine hydrochloride (66 mg, 0.59 mmol), and HATU (242 mg, 0.64 mmol). Then added acetonitrile (1.1 mL) followed by N,N-diisopropylethylamine (0.20 mL, 1.1 mmol) and N-methylmorpholine (0.05 mL, 0.45 mmol). The reaction mixture was stirred at room temperature overnight then concentrated. The crude solid was purified by chromatography over SiO2 with EtOAc/heptane (gradient: 10-80% EtOAc) to afford 112 mg (52%) of [(1R,2R)-1-(3-fluoro-azetidine-1-carbonyl)-2-hydroxy-propyl]-carbamic acid 9H-fluoren-9-ylmethyl ester as a white solid. MS: [M+H]+=399.

1. concentrationthen concentrated
2. customThe crude solid was purified by chromatography over SiO2 with EtOAc/heptane (gradient: 10-80% EtOAc)