Реакция #2467964

Уравнение реакции

K2CO3

dimethylamine

methyl 3-aminothiophene-2-carboxylate

HCl

NaNO2

→

solid

Выход 91.0%

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

Выход 91.0%

Растворители

H2O

H2O

Условия реакции

Обработка

1. 1
   workup.STIRRINGThe mixture was stirred at 0-10° C. for 1 h
2. 2
   workup.ADDITIONpoured into ice cold water
3. 3
   ЭкстракцияThe solution was extracted with chloroform (3×100 mL)
4. 4
   ПромывкаThe combined layer was washed with water, brine
5. 5
   Сушкаdried over sodium sulfate
6. 6
   ФильтрацияThe solution was filtered
7. 7
   Другоеevaporated the solvent
8. 8
   ДругоеThe residue was chromatographed over silica gel column

Методика

To a solution of methyl 3-aminothiophene-2-carboxylate (2.0 g, 12.7 mmol) and conc. HCl (5 mL, 50.8 mmol) in H2O (30 mL) was added NaNO2 (0.96 g, 14.08 mmol) in portions for 5 min at 0° C. After stirring 0.5 h (0-5° C.), the reaction mixture was added to the solution of K2CO3 (6.65 g, 48.26 mmol) and dimethylamine (5.14 mL, 40%, 45.7 mmol) in H2O (36 mL) at 0° C. The mixture was stirred at 0-10° C. for 1 h and poured into ice cold water. The solution was extracted with chloroform (3×100 mL). The combined 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 (80:20) as eluents to give the product as a pale orange color solid (2.5 mg, 91%), mp 74-76° C.

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