Diisopropylethylamine → (R)-3-[8-(3,4-difluoro-benzyloxy)-octanoylamino]-4-dimethylamino-butyric acid benzyl ester

Participants

Reaction Steps

A solution of 8-(3,4-difluoro-benzyloxy)-octanoic acid (153 mg, 0.53 mmol), N,N-diisopropylethylamine (414 mg, 3.21 mmol), and O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium-hexafluorophophate (244 mg, 0.64 mmol) in N,N-dimethylformamide was stirred for 1 h at room temperature, then a solution of (R)-3-amino-4-dimethylamino-butyric acid benzyl ester dihydrochloride (198 mg, 0.64 mmol) in N,N-dimethylformamide (1 mL) was added. The reaction mixture was stirred for 16 h at room temperature, then evaporated. Chromatography (SiO2, dichloromethane-[dichloromethane/methanol/25% aq. ammonia solution 110:10:1] gradient) produced (R)-3-[8-(3,4-difluoro-benzyloxy)-octanoylamino]-4-dimethylamino-butyric acid benzyl ester (136 mg, 50%). Light yellow oil, m/e=505.4 ([M+H]+).

Provenance & Evidence