تفاعل #2467969

معادلة التفاعل

ammonium chloride

methyl 4-methoxy-5-(methoxycarbonyl)-3-nitrothiophene-2-carboxylate

Hydrochloric acid

→

solid

المردود 81.0%

Methyl 3-amino-4-methoxy-5-(methoxycarbonyl)thiophene-2-carboxylate

المردود 81.0%

المذيبات

methanol

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةto cool to rt
2. 2
   ترشيحThe solution was filtered
3. 3
   استخلاصThe solution was extracted with ethyl acetate (4×100 mL)
4. 4
   غسيلThe combined organic layer was washed with brine
5. 5
   تجفيفdried over sodium sulfate
6. 6
   ترشيحThe solution was filtered
7. 7
   أخرىevaporated the solvent

الإجراء التجريبي

To a solution of methyl 4-methoxy-5-(methoxycarbonyl)-3-nitrothiophene-2-carboxylate (0.9 g, 3.27 mmol) in methanol (20 mL) was added conc. Hydrochloric acid (0.3 mL). To the above solution was added iron powder (0.91 g, 16.36 mmol) followed by an aqueous solution of ammonium chloride (0.87 g, 16.3 mmol, water: 5 mL) at rt. The reaction mixture was stirred and warmed to 70° C. for 1 h and was then allowed to cool to rt. The solution was filtered and basified with saturated sodium bicarbonate solution. The solution was extracted with ethyl acetate (4×100 mL). The combined organic layer was washed with brine and dried over sodium sulfate. The solution was filtered and evaporated the solvent to give the product as a pale yellow color solid (0.65 g, 81%), mp 120-124° C. NMR (400 MHz, CDCl3): δ 5.39 (2H, br s), 4.01 (3H, s), 3.87 (3H, s), 3.85 (3H, s); LC-MS (positive ion mode): m/z 246 (M+H)+.

المصدر