反応 #3779

反応方程式

2,3,4-Trimethoxybenzaldehyde

m-chloroperbenzoic acid

→

2,3,4-trimethoxyphenol

収率 51.1%

溶媒

methylene chloride

反応条件

後処理

1. 1
   温度to heat
2. 2
   workup.DISTILLATIONAfter distilling off the solvents under reduced pressure
3. 3
   workup.DISSOLUTIONthe residue was dissolved in ethyl acetate (100 ml)
4. 4
   洗浄washed in an aqueous saturated sodium hydrogen carbonate solution, in water and in a saturated sodium chloride solution
5. 5
   乾燥dried over anhydrous magnesium sulfate
6. 6
   workup.DISTILLATIONThen, the solvents were distilled off under reduced pressure
7. 7
   workup.ADDITIONTo the residue were added dioxane (15 ml)
8. 8
   workup.STIRRINGa 3N sodium hydroxide solution (15 ml), prior to stirring at room temperature for 30 minutes
9. 9
   抽出adjustment to acidity with dilute hydrochloric acid, followed by ethyl acetate extraction three times
10. 10
    洗浄The organic phase was washed in water and in a saturated sodium chloride solution
11. 11
    乾燥dried over anhydrous magnesium sulfate
12. 12
    workup.DISTILLATIONfollowed by distillation of the solvents under reduced pressure
13. 13
    その他The residue was purified by silica gel column chromatography (developing solvent: hexane:ethyl acetate=3:1)

実験手順

2,3,4-Trimethoxybenzaldehyde (5 g) was suspended in anhydrous methylene chloride (50 ml), followed by addition of m-chloroperbenzoic acid (10 g; purity of 70%) to heat and stir the resulting mixture at 50° C. for 3 hours. After distilling off the solvents under reduced pressure, the residue was dissolved in ethyl acetate (100 ml) and washed in an aqueous saturated sodium hydrogen carbonate solution, in water and in a saturated sodium chloride solution, and dried over anhydrous magnesium sulfate. Then, the solvents were distilled off under reduced pressure. To the residue were added dioxane (15 ml) and a 3N sodium hydroxide solution (15 ml), prior to stirring at room temperature for 30 minutes and adjustment to acidity with dilute hydrochloric acid, followed by ethyl acetate extraction three times. The organic phase was washed in water and in a saturated sodium chloride solution and dried over anhydrous magnesium sulfate, followed by distillation of the solvents under reduced pressure. The residue was purified by silica gel column chromatography (developing solvent: hexane:ethyl acetate=3:1), to recover 2,3,4-trimethoxyphenol (2.4 g; yield of 51%). By 1H-NMR (90 MHz, CDCl3), the compound has the peaks shown below.

出典