反応 #54479

反応方程式

sodium acetate

4-Amino-2-bromo-thiazole hydrobromide

trichloroacetyl chloride

pyridine

→

title compound

収率 53.9%

2-Bromo-4-trichloroacetamidothiazole

収率 53.9%

溶媒

methylene chloride

反応条件

後処理

1. 1
   温度maintaining
2. 2
   その他reaction temperature at 0° C. with an ice bath
3. 3
   workup.ADDITIONthe addition
4. 4
   workup.STIRRINGthe reaction mixture was stirred at room temperature for 3 hours
5. 5
   workup.STIRRINGstirred for 30 minutes
6. 6
   その他The mixture was separated
7. 7
   洗浄the organic layer washed with 2N hydrochloric acid, water, sodium carbonate solution and water
8. 8
   乾燥The organic layer was dried (MgSO4)
9. 9
   その他the solvent removed in vacuo
10. 10
    workup.ADDITIONthe residue treated with charcoal in hexane
11. 11
    その他recrystallised from hexane

実験手順

4-Amino-2-bromo-thiazole hydrobromide (15.6 g) and trichloroacetyl chloride (14.3 g) were suspended in methylene chloride (100 ml) with stirring and treated dropwise with pyridine (16 ml) over 15 minutes maintaining reaction temperature at 0° C. with an ice bath. After completing the addition, the reaction mixture was stirred at room temperature for 3 hours, then poured onto 20% aqueous sodium acetate (250 ml) and stirred for 30 minutes. The mixture was separated and the organic layer washed with 2N hydrochloric acid, water, sodium carbonate solution and water. The organic layer was dried (MgSO4) and the solvent removed in vacuo and the residue treated with charcoal in hexane and recrystallised from hexane to give the title compound (10.5 g) m.p. 77°-80° C. (Found: C, 19.0; H, 0.7; N, 8.5. C5H2Cl3BrN2OS requires C, 18.5; H, 0.6; N, 8.6%)

出典