Trifluoroacetic acid → 2-(4-Fluoro-3,5-dimethyl-phenylamino)-hexanoic acid hydroxyamide

Participants

Reaction Steps

To a solution of (R)-2-(4-fluoro-3,5-dimethyl-phenylamino)-hexanoic acid tert-butoxy-amide (0.737 g, 2.273 mmol) in 1 mL of dichloromethane, was added trifluoroacetic acid (9 mL). After stirring at room temperature for 87 h, the reaction mixture was concentrated under reduced pressure. The product was isolated by Flash chromatography (silica gel) eluting with 0-10% methanol/dichoromethane to give the title compound as a white solid (0.182 g, 30% yield). Pure analytical sample was obtained by RP-HPLC purification. LC-MS: tR=6.8 min; m/z 269 (M+H)+;)+; 1H NMR (500 MHz, CD3OD) δ 0.92 (t, J=7.05 Hz, 3H), 1.33-1.45 (m, 4H), 1.71-1.79 (m, 2H), 2.13 (d, J=2.02 Hz, 6H), 3.65 (t, J=7.05 Hz, 1H), 6.36 (d, J=5.88 Hz, 2H); 13C NMR (125.75 MHz, CD3OD) δ 14.24, 14.80, 23.50, 29.18, 33.99, 58.94, 115.65 (d, J=3.14 Hz), 125.69 (d, J=18.74 Hz), 143.30, 155.19 (d, J=233.14 Hz), 172.75; 19F NMR (470.58 MHz, CD3OD) δ −135.79.

Provenance & Evidence