Acetic Acid → Pomalidomide Impurity 10

Participants

Reaction Steps

3-Aminopiperidine-2,6-dione hydrochloride (9.58 g, 58.4 mmol) was dissolved in triethylamine (TEA) (14.7 g) and the mixture was stirred at room temperature for 4 hrs. HOAc (150 mL) and 3-amino-4-hydroxyphthalic acid C1-5 (9.6 g, 48.7 mmol) were added. The mixture was stirred at 120° C. for 20 mins. TEA was added until the white solid was dissolved completely. The mixture was stirred at 120° C. for 2 hrs. After cooling, the solution was extracted with ethyl acetate (500 mL×4). The combined organic layers were dried over Na2SO4, filtered, and concentrated to a dark solid. The dark solid was washed with EA (300 mL) and dried to give compound 1 as a dark solid (7.2 g, yield: 51%). 1H NMR (DMSO-d6, 400 MHz) δ: 11.05 (s, 1H), 10.82 (s, 1H), 6.98 (d, J=8 Hz, 1H), 6.92 (d, J=7.6 Hz, 1H), 5.95 (s, 2H), 5.03-4.98 (m, 1H), 2.91-2.83 (m, 1H), 2.60-2.44 (m, 2H), 2.01-1.98 (m, 1H); MS (ESI+): m/z 290 (M+1); Elem. Anal. Calcd. for C13H11N3O5: C, 53.98; H, 3.83; N, 14.53. Found: C, 53.67; H, 3.80; N, 14.44.

Provenance & Evidence