Diisopropylethylamine → HCID 49823979, compound

Participants

Reaction Conditions

Reaction Steps

(S)-2-Amino-3-(4-benzyloxy-phenyl)-N-tert-butyl-propionamide monohydrochloride (S)-4-Methyl-2-piperidin-1-yl-pentanoic acid monohydrobromide (0.493 g, 1.76 mmol) was mixed with dry DMF (4 mL) under nitrogen atmosphere and cooled to 0° C. in an ice-water bath. To this mixture were added in succession N,N-diisopropylethylamine (1.23 mL, 7.05 mmol ) and solid O-benzotriazol-1-yl-N,N,N',N'-tetramethyluronium hexafluorophosphate (0.667 g, 1.76 mmol ). The resulting reaction mixture was stirred at that temperature for 30 minutes, solid (S)-2-amino-3-(4-benzyloxy-phenyl)-N-tert-butyl-propionamide monohydrochloride (0.639 g, 1.76 mmol) was then added. After stirring for, sequentially, 10 minutes at 0° C. and 45 minutes at ambient temperature, reaction mixture was mixed with 60 mL of diethyl ether; the resulting mixture was successively washed with saturated aqueous NaHCO3 solution (2×60 mL), brine (2×60 mL), and was dried over Na2SO4. The solution was concentrated in vacuo affording an viscous oil. The crude product was further purified by flash chromatography (40% EtOAc in hexane). Recrystallization from EtOAC/hexanes and subsequent drying under vacuum provided 0.4 g (45%) of the pure titled compound as a white crystalline solid.

Provenance & Evidence