3,6-Dimethylphthalic anhydride → 2-(2,6-Dioxopiperid-3-yl)-4,7-dimethylisoindoline-1,3-dione

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Reaction Steps

2-(2,6-Dioxopiperid-3-yl)-4,7-dimethylisoindoline-1,3-dione was prepared by the procedure of Example 1 from 3,6-dimethylphthalic anhydride (220 mg, 1.25 mmol), 3-aminopiperidine-2,6-dione hydrogen chloride (204 mg, 1.24 mmol) and sodium acetate (110 mg, 1.34 mmol) in acetic acid (10 mL). The product is a white solid (200 mg, 56% yield): mp 263.0-265.0° C.; 1H NMR (DMSO-d6) δ2.01-2.07 (m, 1H, CHH), 2.50-2.89 (m, 9H, CH3, CHH, CH2), 5.10 (dd, J=5.1, 12.4 Hz, 1H, NCH), 7.52 (s, 2H, Ar), 11.12 (br s, 1H, NH); 13C NMR (DMSO-d6) δ16.82, 22.02, 30.97, 48.59, 128.01, 135.04, 136.58, 167.68, 169.98, 172.83.

Provenance & Evidence