반응 #160113

반응 방정식

hydrochloric acid

2-isopropyldisulfanylpropane

Butyllithium

4-bromo-3-methyl-benzoic acid

→

4-(isopropylthio)-3-methylbenzoic acid

수율 35.8%

용매

THF

sodium hydroxide

THF

반응 조건

후처리

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   기타30 minutes
3. 3
   기타at room temperature
4. 4
   추출The aqueous layer was then extracted 3 times with ethyl acetate
5. 5
   건조The combined extracts were dried over sodium sulfate
6. 6
   농축concentrated in vacuo
7. 7
   기타The crude material was purified by silica gel column chromatography

실험 절차

Butyllithium (16 mL of 1.6 M, 25.6 mmol) was added dropwise to a mixture of 4-bromo-3-methyl-benzoic acid (2.5 g, 11.6 mmol) and THF (63 mL) at −78° C. The reaction mixture was allowed to stir at −78° C. for 30 minutes before a solution of 2-isopropyldisulfanylpropane (1.7 g, 11.6 mmol) in THF (2 mL) was added dropwise. The mixture was allowed to stir at −78° C. for 30 minutes, then 30 minutes at room temperature. The reaction mixture was then diluted with 1M aqueous sodium hydroxide (100 mL). The organic layer was discarded and the aqueous layer was acidified with 4M aqueous hydrochloric acid. The aqueous layer was then extracted 3 times with ethyl acetate. The combined extracts were dried over sodium sulfate and concentrated in vacuo. The crude material was purified by silica gel column chromatography using a gradient of 0-5% MeOH in dichloromethane to give 4-(isopropylthio)-3-methylbenzoic acid (873 mg, 18%). MS m/z calc. 210.3. Found 211.2 (M+1)+. Retention time: 2.32 minutes (3 min run).

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