Реакция #2467978

Уравнение реакции

water

methyl amine

methyl 3-[(dimethylamino)diazenyl]thiophene-2-carboxylate

→

solid

Выход 76.0%

{3-[(dimethylamino)diazenyl](2-thienyl)}-N-methylcarboxamide

Выход 76.0%

Растворители

THF

THF

Условия реакции

Обработка

1. 1
   workup.ADDITIONThe solution was poured into ice
2. 2
   Экстракцияthe solution was extracted with chloroform (3×100 mL)
3. 3
   ПромывкаThe combined chloroform layer was washed with water, brine
4. 4
   Сушкаdried over sodium sulfate
5. 5
   ФильтрацияThe solution was filtered
6. 6
   Другоеevaporated the solvent
7. 7
   ДругоеThe residue was chromatographed over silica gel column
8. 8
   Другоеto give the product, which
9. 9
   Другоеwas recrystallized from chloroform-hexane

Методика

To an ice cold (0-5° C.) solution of methyl amine (3 mL) in THF (5 mL) was added a solution of methyl 3-[(dimethylamino)diazenyl]thiophene-2-carboxylate (500 mg) in THF (5 mL) for 5 min and stirred at rt for 36 h. The solution was poured into ice cooled water and the solution was extracted with chloroform (3×100 mL). 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 chloroform-methanol (98:2) as eluents to give the product, which was recrystallized from chloroform-hexane gave the product as a pale orange color solid (380 mg, 76%), mp 98-102° C. IR (neat) νmax 3297, 3082, 2929, 1637, 1380, 1348, 1299, 1221, 1109, 1016, 882, 776 cm−1; 1H NMR (400 MHz, CDCl3): δ 8.35 (1H, br s), 7.29 (1H, d, J=5.2 Hz), 7.27 (1H, d, J=5.2 Hz), 3.57 (3H, br s), 3.21 (3H, br s), 3.00 (3H, d, J=4.8 Hz); LC-MS (positive ion mode): m/z 213 (M+H)+.

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