Diisopropylethylamine → (R)-Azepane-1-carboxylic acid {1-(4-[bis-(4-fluoro-phenyl)-methyl]-piperazine-1-carbonyl}-3-methyl-butyl)-amide

Participants

Reaction Conditions

Reaction Steps

(R)-2-[{Azepane-1-carbonyl)-amino]}-4-methyl-pentanoic acid (0.33 g, 1.3 mmol, Example 2, Step B) was dissolved in dry DMF (5 mL) under nitrogen atmosphere and cooled to 0° C. in an ice-water bath. To this solution were added, in succession, N,N-diisopropylethylamine (0.45 mL, 2.6 mmol) and solid O-benzotriazol-1-yl-N,N,N′,N′-tetramethyluronium hexafluorophosphate (0.49 g, 1.3 mmol). The resulting reaction mixture was stirred at that temperature for 30 minutes; solid 1-bis(4-fluorophenyl)methyl piperazine (0.37 g, 1.3 mmol) was then added. After additional 90 minutes stirring at 0° C., reaction mixture was mixed with 60 mL of diethyl ether; the resulting mixture was successively washed with saturated aqueous NaHCO3 solution (2×50 mL), brine (2×50 mL), and dried over Na2SO4. The solution was concentrated in vacuo affording a viscous oil. The crude product was further purified by flash chromatography (60% EtOAc in hexane) to provide 0.58 g (86%) of the pure titled compound as a white foam: mp 71-84° C. APCI-MS m/z 527.3 (MH+).

Provenance & Evidence