반응 #48459

반응 방정식

2-bromopropanoic acid

carbon disulfide

benzylmagnesium chloride

ether

→

title compound ( 20 )

수율 39.0%

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

수율 39.0%

용매

ethyl acetate

tetrahydrofuran

반응 조건

후처리

1. 1
   workup.WAITAfter 48 h
2. 2
   세척washed with water (3×100 mL)
3. 3
   건조The organic layer was dried (magnesium sulfate)
4. 4
   기타evaporated
5. 5
   workup.DISTILLATIONThe remaining liquid was distilled (120°/0.13 Pa, Kugelrohr)
6. 6
   기타to remove unreacted 2-bromopropanoic acid
7. 7
   workup.DISSOLUTIONThe residue was then dissolved in ether (200 mL)
8. 8
   추출extracted with 5% sodium bicarbonate solution (4×50 mL)
9. 9
   세척The combined aqueous extracts were washed with ether (100 mL)
10. 10
    추출The resulting mixture was extracted with ethyl acetate (2×100 mL)
11. 11
    세척the combined organic extracts were washed with water (2×50 mL), saturated sodium chloride (50 mL)
12. 12
    건조dried with magnesium sulfate
13. 13
    기타Evaporation of the solvent

실험 절차

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.

출처