Reaction Steps
To 1-tert-butyl 4-(3-(5-((3-(3-chloro-4-methylphenyl)ureido)methyl)-1-oxoisoindolin-2-yl)-2,6-dioxopiperidin-1-yl)methyl piperidine-1,4-dicarboxylate (300 mg, 0.44 mmol, obtained as described in previous example) was added 2 N HCl in Et2O (15 mL). The slurry was vigorously stirred for 2 h at rt. The solid was filtered, washed with copious Et2O, and dried in a vacuum oven overnight to give (3-(5-((3-(3-chloro-4-methylphenyl)ureido)methyl)-1-oxoisoindolin-2-yl)-2,6-dioxopiperidin-1-yl)methyl piperidine-4-carboxylate Hydrochloride as a white solid (285 mg, 105% yield): HPLC: Waters Symmetry C18, 5 μm, 3.9×150 mm, 1 ml/min, 240 nm, 30/70 CH3CN/0.1% H3PO4, 3.26 min (98.2%); mp: 234-236 0C; 1H NMR (DMSO-d6) δ 1.62-1.81 (m, 2H, CHH, CHH), 1.87-2.01 (m, 2H, CHH, CHH), 2.02-2.16 (m, 1H, CHH), 2.16-2.29 (m, 3H, CH3), 2.32-2.47 (m, 1H, CHH), 2.59-2.76 (m, 1H, CHH), 2.77-2.99 (m, 3H, CHH, CHH, CHH), 3.00-3.28 (m, 3H, CHH, CHH, CHH), 4.15-4.66 (m, 4H, CH2, CH2), 5.26 (dd, J=4.9, 13.2 Hz, 1H, CH), 5.55-5.80 (m, 2H, CH2O), 7.02 (t, J=5.9 Hz, 1H, NH), 7.09-7.29 (m, 2H, Ar), 7.45 (d, J=7.9 Hz, 1H, Ar), 7.53 (s, 1H, Ar), 7.62-7.82 (m, 2H, Ar), 8.41-8.96 (m, 2H, NH, NH), 9.09 (s, 1H. NH); 13C NMR (DMSO-d6) δ 18.73, 21.46, 24.31, 31.24, 37.30, 42.00, 42.73, 47.20, 52.09, 63.40, 116.31, 117.50, 121.91, 122.99, 126.97, 127.27, 130.09, 130.99, 132.96, 139.69, 142.38, 144.94, 155.21, 167.96, 170.19, 171.29, 172.20; LCMS: MH=582, 584: Anal Calcd for C29H33Cl2N5O6+1.6H2O+0.6 HCl+0.2Et2O+0.4t BuCl: C, 53.35; H, 6.05; N, 9.91; Cl, 13.04. Found: C, 53.13; H, 6.06; N, 9.70; Cl, 13.25.
