Reaction Steps
To a stirred suspension of 4-aminomethyl-2-(2,6-dioxo-piperidin-3-yl)-isoindole-1,3-dione hydrochloride (0.7 g, 2.2 mmol) and 2-fluoro-3-trifluoromethyl-benzoyl chloride (0.6 g, 2.8 mmol) in dry methylene chloride (60 mL), was added diisopropylethylamine (0.7 g, 5.4 mmol). The mixture was stirred at room temperature overnight then quenched with methanol (1 mL). The resulting suspension was filtered and the solid was washed with methylene chloride to afford N-[2-(2,6-dioxo-piperidin-3-yl)-1,3-dioxo-2,3-dihydro-1H-isoindol-4-ylmethyl]-2-fluoro-3-trifluoromethyl-benzamide (0.8 g, 72%) as a white solid: mp 155-157° C.; HPLC: Waters Symmetry C-18, 3.9×150 mm, 5 micro, 1 mL/min, 240 nm, 40/60 (CH3CN/H2O): tR=6.23 min. (99%); 1H NMR (DMSO-d6) δ 2.04-2.11 (s, 1H), 2.53-2.64 (m, 2H), 2.85-2.97 (m, 1H), 4.96 (d, J=5.8 Hz, 2H), 5.15-5.21 (dd, J=5.3 and 12.6 Hz, 1H), 7.52 (t, J=7.8 Hz, 1H), 7.79-8.01 (m, 5H), 9.26 (t, J=5.7 Hz, 1H), 11.15 (s, 1H); 13C NMR (DMSO-d6) δ 21.96, 30.91, 38.46, 48.87, 117.03 (117.29, 117.45), 120.65 (124.26), 122.03, 125.09 (125.15), 125.45 (125.64), 127.22, 129.24 (129.29), 131.58, 132.97, 134.89, 138.41, 154.37 (157.77), 162.90, 166.91, 167.45, 169.80, 172.73; Anal. Calcd. for C22H15N3O5F4: C, 55.35; H, 3.17; N, 8.80; F, 15.92. Found: C, 55.13; H, 2.95; N, 8.73; F, 15.69.