반응 #76429

반응 방정식

oxalyl chloride

[2-(2,2-Dimethylpropyl)benzoxazol-5-yl]acetic acid

[(2,2-dimethylpropyl)benzoxazol-5yl]acetic acid

5-amino-4-chloro-3-methylisothiazole

→

N-(4-chloro-3-methylisothiazol-5-yl)-[2-(2,2-dimethylpropyl)benzoxazol-5-yl]acetamide

수율 28.7%

용매

dichloromethane

ethyl acetate

반응 조건

후처리

1. 1
   기타the solvent was removed in vacuo
2. 2
   온도the mixture was heated
3. 3
   온도under reflux for 2 hours
4. 4
   세척washed with brine
5. 5
   건조The organic solution was dried over anhydrous magnesium sulfate
6. 6
   여과filtered
7. 7
   기타the filtrate was evaporated in vacuo
8. 8
   기타The residue was further purified by flash column chromatography on silica gel
9. 9
   세척eluting with a 2:1 mixture of hexane

실험 절차

[2-(2,2-Dimethylpropyl)benzoxazol-5-yl]acetic acid [from step 7] (0.800 g, 0.003 mole) was suspended in dichloromethane (10 ml) and N,N-dimethylformamide (one drop) and oxalyl chloride (0.451 g, 0.004 mole) were added sequentially. The mixture was stirred for 2 hour and then the solvent was removed in vacuo. The residue was taken up in xylene (10 ml), 5-amino-4-chloro-3-methylisothiazole [from step 1] (0.829 g, 0.006 mole) was added and then the mixture was heated under reflux for 2 hours. The mixture was cooled to room temperature, diluted with ethyl acetate and washed with brine. The organic solution was dried over anhydrous magnesium sulfate, filtered and the filtrate was evaporated in vacuo. The residue was further purified by flash column chromatography on silica gel, eluting with a 2:1 mixture of hexane:ethyl acetate, to give N-(4-chloro-3-methylisothiazol-5-yl)-[2-(2,2-dimethylpropyl)benzoxazol-5-yl]acetamide (0.325 g) as a pale orange solid, m.p. 144-145° C.

출처