Reacción #76590

Ecuación de reacción

sodium hydroxide

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

thiourea

→

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

Rendimiento 74.1%

Disolventes

water

ethyl alcohol

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturathe mixture was refluxed for 3 h under a nitrogen atmosphere
2. 2
   Temperaturaat reflux temperature
3. 3
   workup.DISTILLATIONthe ethanol was distilled off under reduced pressure
4. 4
   workup.ADDITIONDiethyl ether (20 mL) was added
5. 5
   Otrothe layers were separated
6. 6
   LavadoThe organic phase was washed with saturated sodium chloride solution (5 mL)
7. 7
   Secadodried over sodium sulfate
8. 8
   Filtraciónfiltered
9. 9
   Concentraciónconcentrated in vacuo

Procedimiento

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.

Fuente