Reaction Steps
1,8 Diazabicyclo[5,4,0]-undec-7-ene (0.8 g, 5.3 mmol) was added to a stirred suspension of 3-(4-aminomethyl-1-oxo-1,3-dihydro-isoindol-2-yl)-piperidine-2,6-dione hydrochloride in acetonitrile (100 mL). The mixture was stirred for 30 minutes. 3-Chlorobenzoyl chloride (0.6 g, 3.2 mmol) was added, and the mixture was stirred at room temperature overnight. The mixture was concentrated and the residue was stirred with CH2Cl2 (60 mL) and 2N HCl (30 mL). The mixture was filtered and the solid was slurried with ethanol (20 mL) to give 3-chloro-N-[2-(2,6-dioxo-piperidin-3-yl)-1-oxo-2,3-dihydro-1H-isoindol-4-ylmethyl]-benzamide (0.8 g, 96%) as a white solid: mp 266-268° C.; 1H NMR (DMSO-d6) δ 2.01-2.06 (m, 1H), 2.37-2.66 (m, 2H), 2.86-2.99 (m, 1H), 4.48 (d, J=17.3 Hz, 1H), 4.53 (d, J=21.1 Hz, 1H), 4.55 (s, 2H), 5.12-5.20 (dd, J=5.0 and 13.2 Hz, 1H, CH), 7.48-7.66 (m, 5H, Ar), 7.87 (d, J=7.7 Hz, 1H, Ar), 7.93 (d, J=1.3 Hz, 1H, Ar), 9.23 (t, J=5.6 Hz, 1H, NH), 11.03 (s, 1H, NH); 13C NMR (DMSO-d6) δ 22.60, 31.20, 39.66, 46.28, 51.60, 121.76, 126.07, 127.08, 128.38, 130.40, 130.77, 131.22, 131.65, 133.23, 134.37, 136.01, 140.21, 164.94, 168.07, 171.04, 172.88; Anal. calcd. for C21H18N3O4Cl: C, 61.24; H, 4.41; N, 10.20; Cl, 8.61. Found: C, 60.92; H, 4.21; N, 10.01; Cl, 8.92.
