反应 #48459

反应方程式

2-bromopropanoic acid

carbon disulfide

benzylmagnesium chloride

ether

→

title compound ( 20 )

收率 39.0%

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

收率 39.0%

溶剂

ethyl acetate

tetrahydrofuran

反应条件

后处理

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

实验过程

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.

来源