反応 #429360

反応方程式

ethyl bromide

magnesium

oxalyl chloride

methylamine methanol

1-bromo-2-(2-tetrahydropyranyloxymethyl)benzene

→

N-methyl-2-oxo-2-[2-(2-tetrahydropyranyloxymethyl)phenyl]acetamide

収率 42.6%

溶媒

water

THF

THF

THF

反応条件

後処理

1. 1
   その他prepared
2. 2
   workup.ADDITIONAfter completion of the addition
3. 3
   温度After cooling
4. 4
   workup.STIRRINGThen, the mixture was stirred at -60° to -70° C. for 40 minutes
5. 5
   workup.STIRRINGthe mixture was stirred at -20° to -10° C. for 30 minutes
6. 6
   workup.ADDITIONwas added
7. 7
   抽出the mixture was extracted with ether (150 ml)
8. 8
   洗浄The extract was washed with saturated brine
9. 9
   乾燥dried over anhydrous magnesium sulfate
10. 10
    濃縮concentrated under reduced pressure
11. 11
    その他The resulting residue was purified by silica gel chromatography (ethyl acetate/n-hexane)

実験手順

A mixed solution of 1-bromo-2-(2-tetrahydropyranyloxymethyl)benzene (2.71 g, 0.01 mol) and dry THF (8 ml) was added dropwise at 50° to 60° C. over 20 minutes to a solution prepared by adding dry THF (2 ml) and ethyl bromide (0.1 ml) to magnesium (0.36 g, 0.015 mol) in a stream of nitrogen. After completion of the addition, the mixture was stirred at 50° to 60° C. for 1 hour and cooled to room temperature. After cooling, the mixture was added dropwise to a mixed solution of oxalyl chloride (1.90 g, 0.015 mol) and dry THF (30 ml) at below -50° C. over 15 minutes. Then, the mixture was stirred at -60° to -70° C. for 40 minutes. A 40% methylamine-methanol solution (4.66 g, 0.06 mol) was added to the reaction mixture, and the mixture was stirred at -20° to -10° C. for 30 minutes. After completion of the reaction, water (150 ml) was added, and the mixture was extracted with ether (150 ml). The extract was washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The resulting residue was purified by silica gel chromatography (ethyl acetate/n-hexane) to obtain N-methyl-2-oxo-2-[2-(2-tetrahydropyranyloxymethyl)phenyl]acetamide(1.18 g, Yield: 42.5%) as a colorless oil.

出典