Reaction #4871

Reaction equation

water

potassium carbonate

ethyl (Z)-2-(2-tritylaminothiazol-4-yl)-2-hydroxyiminoacetate

3-bromo-2-pyrrolidone

→

ethyl (Z)-2-(2-tritylaminothiazol-4-yl)-2-[(2-pyrrolidon-3-yl)oxyimino]acetate

Yield 85.7%

Solvents

dimethylsulfoxide

Conditions

Workup

1. 1
   workup.STIRRINGthe mixture is stirred at room temperature for 20 hours
2. 2
   Othercrystalline precipitates
3. 3
   Filtrationare collected by filtration
4. 4
   Washwashed with water
5. 5
   workup.DISSOLUTIONThe crystals are dissolved in chloroform
6. 6
   Washwashed with water
7. 7
   Otherdried
8. 8
   OtherThen, the chloroform solution is evaporated under reduced pressure
9. 9
   Otherto remove solvent
10. 10
    workup.ADDITION100 ml of ethyl acetate are added to the residue
11. 11
    Otherto stand at room temperature
12. 12
    OtherCrystalline precipitates thus
13. 13
    Otherobtained
14. 14
    Filtrationare collected by filtration
15. 15
    Otherdried

Procedure

15.8 g of ethyl (Z)-2-(2-tritylaminothiazol-4-yl)-2-hydroxyiminoacetate are dissolved in 70 ml of dimethylsulfoxide, and 5.8 g of anhydrous potassium carbonate are added thereto. The mixture is stirred at room temperature for 20 minutes. 6.6 g of 3-bromo-2-pyrrolidone are added to said mixture, and the mixture is stirred at room temperature for 20 hours. The mixture is poured into 800 ml of water, and crystalline precipitates are collected by filtration and washed with water. The crystals are dissolved in chloroform, washed with water and then dried. Then, the chloroform solution is evaporated under reduced pressure to remove solvent. 100 ml of ethyl acetate are added to the residue, and allowed to stand at room temperature. Crystalline precipitates thus obtained are collected by filtration and dried. 16.0 g of ethyl (Z)-2-(2-tritylaminothiazol-4-yl)-2-[(2-pyrrolidon-3-yl)oxyimino]acetate are obtained.

Source