تفاعل #2467972

معادلة التفاعل

K2CO3

dimethylamine

methyl 3-amino-5-phenylthiophene-2-carboxylate

HCl

NaNO2

→

solid

المردود 76.0%

Methyl 3-[(dimethylamino)diazenyl]-5-phenylthiophene-2-carboxylate

المردود 76.0%

المذيبات

H2O

H2O

acetone

ظروف التفاعل

المعالجة

1. 1
   workup.DISSOLUTIONto dissolve the product
2. 2
   workup.STIRRINGThe mixture was stirred at 0-5° C. for 1 h
3. 3
   workup.ADDITIONpoured into ice cold water
4. 4
   استخلاصThe solution was extracted with chloroform (3×100 mL)
5. 5
   غسيلThe combined CHCl3 layer was washed with water, brine
6. 6
   تجفيفdried over sodium sulfate
7. 7
   ترشيحThe solution was filtered
8. 8
   أخرىevaporated the solvent
9. 9
   أخرىThe residue was chromatographed over silica gel column

الإجراء التجريبي

To a solution of methyl 3-amino-5-phenylthiophene-2-carboxylate (5 g, 21.4 mmol) and conc. HCl (9 mL, 85.8 mmol) in H2O (51 mL) was added acetone (30 mL) to dissolve the product. Then NaNO2 (1.7 g, 23.6 mmol) was added in portions for 15 min at 0° C. After stirring at 0-5° C. for 1 h, the reaction mixture was added to the solution of K2CO3 (11.2 g, 81.5 mmol) and dimethylamine (8.5 mL, 40%, 77.2 mmol) in H2O (60 mL) at 0° C. The mixture was stirred at 0-5° C. for 1 h and poured into ice cold water. The solution was extracted with chloroform (3×100 mL). The combined CHCl3 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 pale brown color solid (3.8 g, 76%), mp 92-94° C. 1H NMR (400 MHz, DMSO-d6): δ 7.78-7.80 (2H, m), 7.64 (1H, s), 7.46-7.52 (3H, m), 3.84 (3H, s), 3.60 (3H, s), 3.28 (3H, s); LC-MS (positive ion mode): m/z 290 (M+H)+.

المصدر