反应详情

温度

2.5 °C

To a solution of methyl-amino-5-(methoxycarbonyl)selenophene-2-carboxylate (0.6 g, 2.28 mmol) and conc. HCl (1.0 mL, 9.12 mmol) in water (5.7 mL) was added sodium nitrite (173 mg, 2.51 mmol) in portions for 5 min at 0° C. After stifling at 0-5° C. for 0.5 h, the reaction mixture was added to the solution of potassium carbonate (1.1 g, 8.66 mmol) and dimethylamine (1.0 mL, 40%, 8.21 mmol) in water (6.8 mL) at 0° C. The mixture was stirred at 0-5° C. for 2 h and poured into ice cold water. The solution was extracted with chloroform (3×100 mL) and the combined chloroform layer was washed with water, brine and dried over sodium sulfate. The solution was filtered and evaporated the solvent. The residue was chromatographed over silica gel column using hexane-EtOAc (90:10) as eluents to give the product as a orange color solid (250 g, 34%), mp 122-124° C. 1H NMR (400 MHz, CDCl3): δ 8.29 (1H, s, H-4), 3.88 (3H, s, —COOCH3), 3.87 (3H, s, —COOCH3), 3.52 (3H, s, —N—CH3), 3.28 (3H, s, —N—CH3); LC-MS (positive ion mode): m/z 320, 318 (M+H)+.

1. additionpoured into ice cold water
2. extractionThe solution was extracted with chloroform (3×100 mL)
3. washthe combined chloroform layer was washed with water, brine
4. dry with materialdried over sodium sulfate
5. filtrationThe solution was filtered
6. customevaporated the solvent
7. customThe residue was chromatographed over silica gel column