تفاعل #5331

معادلة التفاعل

Methyl 3,4-diamino-5-methylthiophene-2-carboxylate

triphosgene

→

title compound

Methyl 1,3-dihydro-4-methyl-2-oxo-thieno[3,4-d]imidazole-6-carboxylate

المذيبات

N,N-dimethyl formamide

dichloromethane

ظروف التفاعل

المعالجة

1. 1
   أخرىprecipitates
2. 2
   ترشيحwere collected by filtration
3. 3
   غسيلwashed with dichloromethane
4. 4
   أخرىdried
5. 5
   workup.ADDITIONTo the suspension was added sodium hydride (60% in oil; 0.55 g)
6. 6
   workup.STIRRINGthe mixture was stirred for three days at room temperature
7. 7
   أخرىThe solvent was evaporated under reduced pressure
8. 8
   workup.ADDITIONTo the residue was added 2N-HCl
9. 9
   أخرىResulting
10. 10
    أخرىprecipitates
11. 11
    ترشيحwere collected by filtration
12. 12
    غسيلwashed with water, ether and methanol successively
13. 13
    أخرىby drying

الإجراء التجريبي

Methyl 3,4-diamino-5-methylthiophene-2-carboxylate (3.0 g) was dissolved in a mixture of N,N-dimethyl formamide (5 ml) and dichloromethane (15 ml). To the solution was added triphosgene (2.4 g) in portions. The mixture was stirred for two days at room temperature, and precipitates were collected by filtration, washed with dichloromethane and dried. Resultant white powder (2.4 g) was suspended in N,N-dimethylformamide (25 ml). To the suspension was added sodium hydride (60% in oil; 0.55 g), and the mixture was stirred for three days at room temperature. The solvent was evaporated under reduced pressure. To the residue was added 2N-HCl. Resulting precipitates were collected by filtration, washed with water, ether and methanol successively, followed by drying to afford the title compound (82 g, 53%) as pale brown powder.

المصدر