تفاعل #443812

معادلة التفاعل

5-bromo-o-anisaldehyde

ethylene glycol

ethylene glycol

→

2-(5-bromo-2-methoxyphenyl)-1,3-dioxolane

المردود 126.5%

المذيبات

toluene

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةat reflux for 21 hr
2. 2
   درجة الحرارةheated
3. 3
   درجة الحرارةat reflux for 6 hr
4. 4
   غسيلThe resulting solution was washed with sat. NaHCO3, water and brine
5. 5
   تجفيفdried over MgSO4
6. 6
   تركيزconcentrated in vacuo

الإجراء التجريبي

A solution of 5-bromo-o-anisaldehyde (49.7 g, 231 mmol), ethylene glycol (17.2 g, 277 mmol) and p-toluene sulfonic acid (4.3 g, 23 mmol) in dry toluene (400 ml) was heated at reflux for 21 hr. And then ethylene glycol (4.3 g, 70 mmol) was added to the reaction mixture and heated at reflux for 6 hr. The resulting solution was washed with sat. NaHCO3, water and brine, dried over MgSO4 and concentrated in vacuo to give crude 2-(5-bromo-2-methoxyphenyl)-1,3-dioxolane (75.7 g) as a dark red oil. The residue was added NaHCO3 and then distilled to give 2-(5-bromo-2-methoxyphenyl)-1,3-dioxolane (52.8 g, 88.3%) as a colorless oil.

المصدر