Reaction Steps
A mixture of 2-[1-(3-ethoxy-4-methoxyphenyl)-2-methylsulfonylethyl]-4-nitroisoindoline-1,3-dione (710 mg, 1.58 mmol) and Pd/C (200 mg) in ethyl acetate/acetone (40 mL each) was shaken under H2 (50 psi) in a Parr Type Shaker for 5 hours. The suspension was filtered through a pad of magnesium sulfate. The filtrate was concentrated in vacuo to give an oil. The oil was stirred with ethyl acetate (a mL), hexane (2 mL) and ether (2 ML)for 1 h. The resulting suspension was filtered and the solid was dried in a vacuum oven to give 2-[1-(3-ethoxy-4-methoxyphenyl)-2-methylsulfonylethyl]-4-aminoisoindoline-1,3-dione as a yellow solid (550 mg, 83% yield): mp, 135.0-137.5° C.; 1H NMR (DMSO-d6); δ 1.32 (t, J=6.9 Hz, 3H, CH3), 3.00 (s, 3H, CH3), 3.73 (s, 3H, CH3), 4.00 (q, J=6.9 Hz, 2H, CH2), 4.08 (dd, J=4.2, 14.5 Hz, 1H, CHH), 4.36 (dd, J=10.8, 14.2 Hz, 1H, CHH), 5.72 (dd, J=4.1, 10.3 Hz, 1H, NCH), 6.51(br s, SH, NH2), 6.89-7.07 (m, 5H, Ar), 7.43 (t, J=7.4, Hz, 1H, Ar); 13C NMR (CDCl3) δ 14.68, 41.55, 48.62, 55.23, 55.93, 64.48, 110.70, 111.42, 112.52, 112.96, 120.38, 121.30, 129.95, 132.23, 135.37, 145.56, 148.56, 149.56, 168.19, 169.43; Anal Calcd for C20H22NO6S: C, 57.41; H, 5.30; N, 6.69. Found C, 57.11; H, 5.23; N, 6.43.
