反应详情

A solution of 3-amino-2,6-dihydro-4H-pyrrolo[3,4-c]pyrazole-5-carboxylic acid tert-butyl ester (1 g; 4.46 mmol; 1 eq.) and 3-chloroacetylacetone (0.71 mL; 6.24 mmol; 1.4 eq.) in AcOH (10 mL) was stirred at room temperature for 18 hours. The reaction was poured into water (100 mL) under vigorous stirring and the precipitate filtered off, washed with water (3×) and dried to afford the title compound (1298 mg, 90%) as an off-white solid. 1H NMR (DMSO-d6) δ 4.60-4.52 (m, 4H), 2.81 (br s, 3H), 2.60-2.57 (m, 3H), 1.48 (s, 9H). HPLC (max plot) 98.4%; Rt 3.96 min. UPLC/MS: (MS+) 323 ([M+H]+).

1. filtrationthe precipitate filtered off
2. washwashed with water (3×)
3. customdried