Reaction Steps
A mixture of 3-(1,3-dioxo-4-pyrrolylisoindolin-2-yl)-3-(3-ethoxy-4-methoxyphenyl)propanoic acid (1.29 g, 2.97 mmol), and carbonyldiimidazole (481 mg, 2.97 mmol) in tetrahydrofuran (13 mL) was stirred at room temperature for 2 h. To the mixture was added dimethylamine in tetrahydrofuran (1.7 mL, 2N, 3.4 mmol) and the mixture stirred for an additional 2 h. Water (70 mL) and methylene chloride (50 mL) was added to the mixture. The organic layer was separated, washed with brine (20 mL), and dried over magnesium sulfate. The solvent was removed in vacuo to give a brown solid. This solid was purified by column chromatography (silica gel, 1:5 ethyl acetate:methylene chloride +0.1% MeOH) to give 3-(1,3-dioxo-4-pyrrolylisoindolin-2-yl)-3-(3-ethoxy-4-methoxyphenyl)-N,N-dimethylpropanamide as a yellow solid (750 mg, 55% yield): mp, 105-107° C.; 1H NMR (CDCl3) δ 1.43 (t, J=7 Hz, 3H, CH3), 2.88 (s, 3H, CH3), 3.00 (s, 3H, 2CH3), 3.04 (dd, J=4.9, 16 Hz, 1H, CHH), 3.82 (s, 3H, CH3), 3.91 (dd, J=10.2, 16.6 Hz, 1H, CHH), 4.09 (q, J=7 Hz, 2H, CH2), 5.82 (dd, J=4.9, 10.2 Hz, 1H, NCH), 6.35 (t, J=2 Hz, 2H, Ar), 6.77-6.81 (m, 1H, Ar), 7.11-7.15 (m, 4H, Ar), 7.52-7.56 (m, 1H, Ar), 7.63-7.71 (m, 2H, Ar); 13C NMR (CDCl3) δ 14.65, 34.71, 35.34, 37.02, 51.52, 55.83, 64.32, 110.48, 111.22, 112.76, 120.24, 120.66, 121.35, 122.02, 129.75, 132.00, 134.06, 134.94, 138.23, 148.15, 148.93, 166.19, 167.34, 169.58; Anal Calcd for C26H27N3O5+0.15 H2O: C, 67.30; H, 5.99; N, 8.85. Found: C, 67.16; H, 5.88; N, 8.92.
