Réaction #1960494

Équation de réaction

hydrochloric acid

7,8-difluoro-2-pentyl-6-[1-(4-propylcyclohexyl)prop-2-ynyloxy]chroman

potassium fluoride

water

→

5,6-difluoro-3-pentyl-8-(4-propylcyclohexyl)-1,2,3,8-tetrahydropyrano[3,2-f]chromene

Solvants

N,N-diethylaniline

Conditions de réaction

Traitement

1. 1
   TempératureAfter cooling
2. 2
   ExtractionThe batch is extracted with MTBE
3. 3
   Lavagethe organic phase is washed with saturated sodium chloride solution
4. 4
   AutreThe solution is dried
5. 5
   Autreevaporated to dryness
6. 6
   AutreThe crude product is purified by column chromatography (SiO2, 1-chlorobutane:pentane=4:1)

Mode opératoire

9.7 g (23.2 mmol) of 7,8-difluoro-2-pentyl-6-[1-(4-propylcyclohexyl)prop-2-ynyloxy]chroman are heated at 200° C. for 6 h together with 2.7 g (46.5 mmol) of potassium fluoride in 75 ml of N,N-diethylaniline. After cooling, water is added, and the mixture is acidified using 25% hydrochloric acid. The batch is extracted with MTBE, and the organic phase is washed with saturated sodium chloride solution. The solution is dried using sodium sulfate and evaporated to dryness. The crude product is purified by column chromatography (SiO2, 1-chlorobutane:pentane=4:1), giving 5,6-difluoro-3-pentyl-8-(4-propylcyclohexyl)-1,2,3,8-tetrahydropyrano[3,2-f]chromene as a pale-brown oil.

Source