반응 #446010

반응 방정식

nitric acid

4-chloro-2,2-di-methyl-2,3-dihydro-7-benzofurancarboxylic acid

→

desired subtitle intermediate

4-chloro-5-nitro-2,2-dimethyl-2,3-dihydro-7-benzofurancarboxylic acid

용매

sulfuric acid

반응 조건

후처리

1. 1
   workup.ADDITIONthe mixture was added to ice
2. 2
   workup.STIRRINGwith stirring
3. 3
   여과The resulting solid was collected by filtration
4. 4
   세척washed with water
5. 5
   기타After air drying
6. 6
   기타the residue was crystallized twice from ethyl acetate/hexane

실험 절차

To a mixture of 40 ml of nitric acid and 40 ml of sulfuric acid cooled to 5° C. by means of an external ice bath were added 10 g of 4-chloro-2,2-di-methyl-2,3-dihydro-7-benzofurancarboxylic acid over a period of 28 minutes. After stirring at 5° C. for 10 minutes, the mixture was added to ice with stirring. The resulting solid was collected by filtration and washed with water. After air drying, the residue was crystallized twice from ethyl acetate/hexane to provide 3.5 g of the desired subtitle intermediate, m.p. 260°-262° C.

출처