Reaction #2467977

Reaction equation

water

ethanol amine

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

→

solid

Yield 77.0%

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

Yield 77.0%

Solvents

THF

THF

Conditions

Workup

1. 1
   workup.ADDITIONThe solution was poured into ice
2. 2
   Extractionthe solution was extracted with ethyl acetate (3×50 mL)
3. 3
   WashThe combined EtOAc layer was washed with water, brine
4. 4
   Dryingdried over sodium sulfate
5. 5
   FiltrationThe solution was filtered
6. 6
   Otherevaporated the solvent
7. 7
   OtherThe residue was chromatographed over silica gel column
8. 8
   Otherto give the product, which
9. 9
   Otherwas recrystallized from chloroform-hexane

Procedure

To an ice cold (0-5° C.) solution of ethanol amine (5 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 20 h. The solution was poured into ice cooled water and the solution was extracted with ethyl acetate (3×50 mL). The combined EtOAc 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 (95:5) as eluents to give the product, which was recrystallized from chloroform-hexane gave the product as a pale orange color solid (430 mg, 77%), mp 118-122° C. IR (neat) νmax, 3397, 3278, 2926, 1621, 1353, 1298, 1220, 1083, 1007, 882, 775 cm−1;

Source