تفاعل #41916

معادلة التفاعل

potassium carbonate

pyridinium p-toluenesulfonate

2-bromo-4-fluorophenol

sodium chloride

3,4-dihydropyran

→

2-Bromo-4-fluoro-1-(tetrahydropyran-2-yloxy)benzene

المذيبات

water

dichloromethane

dichloromethane

ظروف التفاعل

المعالجة

1. 1
   أخرىThe organic phase was removed
2. 2
   تجفيفdried over potassium carbonate
3. 3
   workup.DISTILLATIONfractionally distilled (approx. 1 mbar, top temperature from 79 to 82° C.) by means of a Vigreux column (40 cm)
4. 4
   أخرىThe product was obtained as a colorless, low-viscosity oil

الإجراء التجريبي

A mixture of 478.0 ml (5.24 mol) of 3,4-dihydropyran and 750 ml of dichloromethane was admixed with 65.4 g (260 mmol) of pyridinium p-toluenesulfonate. Subsequently, a solution of 500.0 g (2.62 mmol) of 2-bromo-4-fluorophenol in 500 ml of dichloromethane was added dropwise. After stirring for 24 h, the reaction mixture was admixed with a solution of 50 g of potassium carbonate in 500 ml of water, and then with 500 ml of saturated sodium chloride solution. The organic phase was removed, dried over potassium carbonate and, after freeing it of the solvent and potassium carbonate, fractionally distilled (approx. 1 mbar, top temperature from 79 to 82° C.) by means of a Vigreux column (40 cm). The product was obtained as a colorless, low-viscosity oil. The yield was 520.5 g (72.2%) at a purity of greater than 98.0% by 1H NMR.

المصدر