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 (0.7 g, 2.1 mmol) in acetonitrile (100 mL). The mixture was stirred for 30 minutes, and benzoyl chloride (0.4 g, 3.2 mmol) was added. The mixture was stirred at room temperature overnight. The mixture was concentrated and the residue was stirred with 2N HCl (30 mL) and CH2Cl2 (80 mL). The solid was collected to give N-[2-(2,6-dioxo-piperidin-3-yl)-1-oxo-2,3-dihydro-1H-isoindol-4-ylmethyl]-benzamide (0.5 g, 68%) as a white solid: mp 228-230° C.; 1H NMR (DMSO-d6) δ 2.01-2.05 (m, 1H), 2.33-2.65 (m, 2H), 2.86-3.00 (m, 1H), 4.48 (d, J=17.3 Hz, 1H), 4.53 (d, J=22.1 Hz, 1H), 4.55 (s, 2H), 5.12-5.19 (dd, J=5.0 and 13.2 Hz, 1H, CH), 7.44-7.65 (m, 6H, Ar), 7.87 (d, J=7.1 Hz, 2H, Ar), 9.11 (t, J=5.7 Hz, 1H, NH), 11.03 (s, 1H, NH); 13C NMR (DMSO-d6) δ 22.61, 31.20, 46.30, 51.60, 121.67, 127.25, 128.35, 130.67, 131.36, 131.63, 134.07, 134.74, 140.16, 166.37, 168.10, 171.04, 172.88; Anal. calcd. for C21H19N3O4: C, 66.83; H, 5.07; N, 11.13. Found: C, 66.58; H, 5.08; N, 11.12.
