反应详情

1-(4-Fluoro-3-(trifluoromethyl)phenyl)-1-(3-fluoro-5-(trifluoromethyl)phenyl)-2-phenylethanamine (300 mg, 0.67 mmol) and cyclopentyl isocyanate (0.4 mL, 5.3 eq) were stirred in 1,4-dioxane (2 mL) at room temperature overnight. The reaction mixture was concentrated, and purified by flash chromatography (silica gel, hexanes/EtOAc) to give the racemic mixture of 1-cyclopentyl-3-(1-(4-fluoro-3-(trifluoromethyl)phenyl)-1-(3-fluoro-5-(trifluoromethyl)phenyl)-2-phenylethyl)urea (250 mg, yield: 67%). The racemate (250 mg) was dissolved in 10% isopropanol in heptane, and was resolved by chiral prep HPLC using an AD column (10% isopropanol/heptane/0.1% DEA, isocratic) to give the fast eluting enantiomer 1 (110 mg) corresponding to (S)-1-cyclopentyl-3-(1-(4-fluoro-3-(trifluoromethyl)phenyl)-1-(3-fluoro-5-(trifluoromethyl)phenyl)-2-phenylethyl)urea, (analytical chiral HPLC (AD, 10% isopropanol/heptane/0.1% DEA, isocratic), retention time=4.85 min) and the slow eluting enantiomer 2 (105 mg) corresponding to (R)-1-cyclopentyl-3-(1-(4-fluoro-3-(trifluoromethyl)phenyl)-1-(3-fluoro-5-(trifluoromethyl)phenyl)-2-phenylethyl)urea, (analytical chiral HPLC (AD, 10% isopropanol/heptane/0.1% DEA, isocratic), retention time=14.11 min) LCMS (10-90% MeOH in H2O with 0.1% TFA in a 4-min run), retention time=4.33 min, 557.32 (M+H); 1H NMR (400 MHz, CDCl3) δ ppm 7.36-7.44 (m, 2H), 7.23-7.29 (m, 3H), 7.13-7.21 (m, 4H), 6.68-6.74 (m, 2H), 4.84 (s, 1H), 4.40 (s, br, 1H), 3.84-3.95 (m, 3H), 1.88-1.98 (m, 2H), 1.56-1.68 (m, 4H), 1.34 (d, J=6.36 Hz, 2H).

1. concentrationThe reaction mixture was concentrated
2. custompurified by flash chromatography (silica gel, hexanes/EtOAc)
3. customto give