반응 #76590

반응 방정식

sodium hydroxide

5-bromo-2,2-dimethylpentanoic acid ethyl ester

thiourea

→

5-mercapto-2,2-dimethylpentanoic acid ethyl ester

수율 74.1%

용매

water

ethyl alcohol

반응 조건

후처리

1. 1
   온도the mixture was refluxed for 3 h under a nitrogen atmosphere
2. 2
   온도at reflux temperature
3. 3
   workup.DISTILLATIONthe ethanol was distilled off under reduced pressure
4. 4
   workup.ADDITIONDiethyl ether (20 mL) was added
5. 5
   기타the layers were separated
6. 6
   세척The organic phase was washed with saturated sodium chloride solution (5 mL)
7. 7
   건조dried over sodium sulfate
8. 8
   여과filtered
9. 9
   농축concentrated in vacuo

실험 절차

To a solution of 5-bromo-2,2-dimethylpentanoic acid ethyl ester (2.41 g, 10 mmol) in ethyl alcohol (5 mL) was added thiourea (0.77 g, 10 mmol) and the mixture was refluxed for 3 h under a nitrogen atmosphere. A solution of sodium hydroxide (0.62 g, 15 mmol) in deionized water (2.5 mL) was added and stirring was continued for another 2 h at reflux temperature. The mixture was cooled to rt and the ethanol was distilled off under reduced pressure. Diethyl ether (20 mL) was added and the layers were separated. The organic phase was washed with saturated sodium chloride solution (5 mL), dried over sodium sulfate, filtered, and concentrated in vacuo to give 5-mercapto-2,2-dimethylpentanoic acid ethyl ester (1.41 g, 74%) as a yellow oil. 1H NMR (300 MHz, CDCl3/TMS): d (ppm): 4.12 (q, J=7.0 Hz, 2H), 2.57-2.43 (m, 2H), 1.69-1.45 (t, 4H), 1.25 (t, J=7.0 Hz, 3H), 1.17 (s, 7H). 13C NMR(75 MHz, CDCl3/TMS): d (ppm): 177.55, 41.0, 39.24, 25.07, 24.90, 14.18.

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