반응 #1909781

반응 방정식

hexane

2,4-dihydroxy-3-methylbenzoic acid methyl ester

tert-butyl hypochlorite

→

title compound

수율 37.0%

5-Chloro-2,4-dihydroxy-3-methylbenzoic acid

수율 37.0%

용매

ethyl acetate

반응 조건

후처리

1. 1
   온도cooling
2. 2
   온도the mixture was cooled with ice
3. 3
   기타precipitation of crystals
4. 4
   여과The crystals were collected by filtration
5. 5
   workup.DISSOLUTIONdissolved in a mixed solvent of methanol (20 ml) and tetrahydrofuran (THF, 20 ml)
6. 6
   workup.ADDITIONA 1M lithium hydroxide solution (40 ml) was added to the solution
7. 7
   온도the mixture was refluxed
8. 8
   온도under heating for 18 hours
9. 9
   농축The reaction mixture was concentrated
10. 10
    workup.ADDITIONa 10% aqueous citric acid solution was added to the residue, which
11. 11
    추출was followed by extraction with ethyl acetate
12. 12
    세척The organic layer was washed with water and saturated brine
13. 13
    건조dried over anhydrous sodium sulfate
14. 14
    농축The organic layer was concentrated under reduced pressure

실험 절차

To a solution of 2,4-dihydroxy-3-methylbenzoic acid methyl ester (9.9 g) in ethyl acetate (100 ml) was added tert-butyl hypochlorite (12.3 ml) under ice-cooling. After stirring for 2 hours, hexane (200 ml) was added, and the mixture was cooled with ice to allow precipitation of crystals. The crystals were collected by filtration, and dissolved in a mixed solvent of methanol (20 ml) and tetrahydrofuran (THF, 20 ml). A 1M lithium hydroxide solution (40 ml) was added to the solution, and the mixture was refluxed under heating for 18 hours. The reaction mixture was concentrated, and a 10% aqueous citric acid solution was added to the residue, which was followed by extraction with ethyl acetate. The organic layer was washed with water and saturated brine, and dried over anhydrous sodium sulfate. The organic layer was concentrated under reduced pressure to give the title compound (4.14 g, yield 37%).

출처