反応 #48459

反応方程式

2-bromopropanoic acid

carbon disulfide

benzylmagnesium chloride

ether

→

title compound ( 20 )

収率 39.0%

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

収率 39.0%

溶媒

ethyl acetate

tetrahydrofuran

反応条件

後処理

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

実験手順

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.

出典