تفاعل #1596944

معادلة التفاعل

ethanol

bismuth(III) bromide

4-benzyloxy-3-fluorobenzaldehyde

2-vinylpentan-1-ol

→

2-(4-benzyloxy-3-fluorophenyl)-4-bromo-5-propyltetrahydropyran

المذيبات

chlorobutane

dichloromethane

ظروف التفاعل

المعالجة

1. 1
   أخرىInsoluble constituents are separated off
2. 2
   ترشيحthe mixture is filtered absorptively (SiO2, CH2Cl2)
3. 3
   تركيزThe filtrate is concentrated to dryness
4. 4
   أخرىthe residue is purified by column chromatography (SiO2, n-heptane:MTBE=4:1)
5. 5
   أخرىThe oil obtained
6. 6
   أخرىThe crystals which deposit are collected
7. 7
   أخرىrecrystallised again from n-heptane

الإجراء التجريبي

188.0 g (0.79 mol) of 4-benzyloxy-3-fluorobenzaldehyde are initially introduced in 1000 ml of dichloromethane at 0° C. together with 90.0 g (0.79 mol) of 2-vinylpentan-1-ol. 176.0 g (0.39 mol) of bismuth(III) bromide are added in portions, and the mixture is stirred at room temperature for 19 h. Insoluble constituents are separated off, and the mixture is filtered absorptively (SiO2, CH2Cl2). The filtrate is concentrated to dryness, and the residue is purified by column chromatography (SiO2, n-heptane:MTBE=4:1). The oil obtained is taken up in chlorobutane, and the solution is added dropwise to cold ethanol. The crystals which deposit are collected and recrystallised again from n-heptane. In this way, 2-(4-benzyloxy-3-fluorophenyl)-4-bromo-5-propyltetrahydropyran is obtained as a yellowish solid.

المصدر