Reaction Steps
To a stirred suspension of 4-aminomethyl-2-(2,6-dioxo-piperidin-3-yl)-isoindole-1,3-dione hydrochloride (0.7 g, 2.16 mmol) in CH2Cl2 (60 ml), was added diisopropylethylamine (0.94 mL, 5.4 mmol) and 4-chlorobenzoyl chloride (0.5 g, 2.8 mmol). The mixture was stirred at room temperature overnight and a suspension was obtained. The reaction mixture was quenched with MeOH (1 mL). The suspension was then filtered, and the solid was rinsed with CH2Cl2 (10 mL) to afford 4-chloro-N-[2-(2,6-dioxo-piperidin-3-yl)-1,3-dioxo-2,3-dihydro-1H-isoindol-4-ylmethyl]-benzamide as a white solid (0.5 g, 52%): mp, 233-235° C.; HPLC: Waters Symmetry C-18, 3.9×150 mm, 5 micro, 1 mL/min, 240 nm, 40/60 (CH3CN/H2O): tR=4.7 min. (99%); 1H NMR (DMSO-d6): δ 2.06-2.11 (m, 1H), 2.53-2.64 (m, 2H), 2.84-2.93 (m, 1H), 4.95 (d, J=5.8 Hz, 2H), 5.15-5.20 (dd, J=5, 12 Hz, 1H), 7.56-7.59 (dd, J=1.7, 6.8 Hz, 2H), 7.72-7.83 (m, 3H), 7.93-7.96 (dd, J=1.8, 6.8 Hz, 2H), 9.23 (t, J=6 Hz, 1H), 11.15 (s, 1H). 13C NMR (DMSO-d6) δ: 21.97, 30.92, 38.38, 48.86, 121.90, 127.15, 128.45, 129.25, 131.53, 132.65, 133.09, 134.80, 136.28, 139.08, 165.57, 166.94, 167.51, 169.81, 172.74. Anal Calcd for C21H16ClN3O5: C, 59.23; H, 3.79; N, 9.87; Cl, 8.33. Found: C, 59.27; H, 3.42; N, 9.75; Cl, 8.57.
