Diisopropylethylamine → (s)-2-Hydroxy-4-methyl-pentanoic acid [4,4-bis-(4-fluoro-phenyl)-butyl]-amide

Participants

Reaction Steps

L-2-hydroxyisocaproic acid (102 mg, 0.77 mmol) was dissolved in DMF (5 mL) and treated with N,N-diisopropylethylamine (0.53 mL, 3.06 mmol), 4,4-bis-(4-fluorophenyl)-butylamine (200 mg, 0.77 mmol), and HBTU (292 mg, 0.77 mmol), then stirred overnight at room temperature. The reaction was diluted with EtOAc (125 mL), washed with saturated bicarbonate solution and brine, dried over Na2SO4, and concentrated. The residue was chromatographed twice on silica gel, eluting with 2-4% MeOH/CH2Cl2 to give 139 mg (48%) of the desired product as an oil. MS: 376.2 (M+1 for C22H27N1O2F2); an oil; TLC (SiO2), Rf 0.73 (8% MeOH/CH2Cl2); HPLC (7:3 CH3CN/H2O with 0.1% TFA, C-18 column) 96.46%, RT=5.448 min.

Provenance & Evidence