反応 #588891

反応方程式

2-Bromo-5-methoxybenzaldehyde

triethylorthoformate

p-Toluenesulfonic acid monohydrate

→

1-bromo-2-(dimethoxymethyl)-4-methoxybenzene

収率 53.0%

溶媒

methanol

反応条件

後処理

1. 1
   温度under reflux for 5 h
2. 2
   その他The reaction was quenched with aqueous NaHCO3
3. 3
   抽出extracted with DCM
4. 4
   乾燥The combined organic phases were dried over Na2SO4
5. 5
   ろ過filtered
6. 6
   濃縮concentrated in vacuum at the temperature
7. 7
   その他exceeding 35° C
8. 8
   その他The residue was purified by silica gel chromatography

実験手順

Step AH (2): 2-Bromo-5-methoxybenzaldehyde (1069 mg, 4.975 mmol) was dissolved in a mixture of methanol (20 mL) and triethylorthoformate (20 mL). p-Toluenesulfonic acid monohydrate (180.0 mg, 0.946 mmol) was added and the reaction mixture was stirred under reflux for 5 h. The reaction was quenched with aqueous NaHCO3 and extracted with DCM. The combined organic phases were dried over Na2SO4, filtered and concentrated in vacuum at the temperature, not exceeding 35° C. The residue was purified by silica gel chromatography to give 1-bromo-2-(dimethoxymethyl)-4-methoxybenzene (688.5 mg, 53%) as colorless oil. LC-MS (M+H)+=261.00. 1H NMR (CDCl3, 500 MHz) δ 7.42 (d, J=7.0 Hz, 1H) 7.16 (d, J=3.0 Hz, 1H) 6.76 (dd, J1=10 Hz, J2=3.0 Hz, 1H) 5.50 (s, 1H) 3.80 (s, 3H) 3.39 (s, 6H).

出典