Diisopropylethylamine → (s)-Azepane-1-carboxylic acid (1-{4-[bis-(4-fluoro-phenyl)-methyl]-piperazine-1-carbonyl}-2-methyl-butyl)-amide

Participants

Reaction Conditions

Reaction Steps

(S)-2-[(Azepane-1-carbonyl)-amino]-3-methyl-pentanoic acid (0.300 g, 1.17 mmol, Example 16, Step B) was dissolved in dry DMF (4 mL) under nitrogen atmosphere and cooled to 0° C. in an ice-water bath. To this solution were added, in succession, N,N,-diisopropylethylamine (0.408 mL, 2.34 mmol) and solid O-benzotriazol-1-yl-N,N,N′,N′-tetramethyluronium hexafluorophosphate (0.444 g, 1.17 mmol). The resulting reaction mixture was stirred at that temperature for 35 minutes; solid 1-bis(4-fluorophenyl)methyl piperazine (0.337 g, 1.17 mmol) was then added. After stirring for, sequentially, 10 minutes at 0° C. and 30 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 a viscous oil. The crude product was further purified by flash chromatography (40% EtOAc in hexane, then 60% EtOAc in hexane) to provide 0.536 g (87%) of the pure titled compound as a white foam: mp 64-77° C. APCI-MS m/z 527.4 (MH+).

Provenance & Evidence