Реакция #48459

Уравнение реакции

2-bromopropanoic acid

carbon disulfide

benzylmagnesium chloride

ether

→

title compound ( 20 )

Выход 39.0%

2-[(2-phenylethanethioyl)sulfanyl]propanoic Acid

Выход 39.0%

Растворители

ethyl acetate

tetrahydrofuran

Условия реакции

Обработка

1. 1
   workup.WAITAfter 48 h
2. 2
   Промывкаwashed with water (3×100 mL)
3. 3
   СушкаThe organic layer was dried (magnesium sulfate)
4. 4
   Другоеevaporated
5. 5
   workup.DISTILLATIONThe remaining liquid was distilled (120°/0.13 Pa, Kugelrohr)
6. 6
   Другоеto remove unreacted 2-bromopropanoic acid
7. 7
   workup.DISSOLUTIONThe residue was then dissolved in ether (200 mL)
8. 8
   Экстракцияextracted with 5% sodium bicarbonate solution (4×50 mL)
9. 9
   ПромывкаThe combined aqueous extracts were washed with ether (100 mL)
10. 10
    ЭкстракцияThe resulting mixture was extracted with ethyl acetate (2×100 mL)
11. 11
    Промывкаthe combined organic extracts were washed with water (2×50 mL), saturated sodium chloride (50 mL)
12. 12
    Сушкаdried with magnesium sulfate
13. 13
    ДругоеEvaporation of the solvent

Методика

A solution of benzylmagnesium chloride in ether (1.0 M, 40 mL, 40 mmol) was added slowly with stirring to an ice-cooled solution of carbon disulfide (4.0 mL, 66 mmol) in dry tetrahydrofuran (40 mL) under nitrogen. After 30 min, 2-bromopropanoic acid (3.6 mL, 6.2 g, 40 mmol) was added and the reaction was stirred at ambient temperature. After 48 h, the mixture was poured into ethyl acetate (200 mL) and washed with water (3×100 mL), followed by saturated sodium chloride solution (100 mL). The organic layer was dried (magnesium sulfate) and evaporated. The remaining liquid was distilled (120°/0.13 Pa, Kugelrohr) to remove unreacted 2-bromopropanoic acid. The residue was then dissolved in ether (200 mL) and extracted with 5% sodium bicarbonate solution (4×50 mL). The combined aqueous extracts were washed with ether (100 mL), then acidified to pH<1 with 2 M hydrochloric acid. The resulting mixture was extracted with ethyl acetate (2×100 mL) and the combined organic extracts were washed with water (2×50 mL), saturated sodium chloride (50 mL) and then dried with magnesium sulfate. Evaporation of the solvent gave the title compound (20) as a red liquid (3.73 g, 39%) which slowly solidified on standing.

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