Reaction #2109

Reaction equation

diethyl 5-hydroxypentylphosphonate

3,4-dihydropyran

pyridinium toluene-4-sulfonate

→

Diethyl 5-(tetrahydropyran-2-yloxy)pentylphosphonate

Solvents

dichloromethane

Conditions

Workup

1. 1
   Temperatureunder reflux for 16 hours
2. 2
   WashThe solution was washed with water and saturated sodium hydrogen carbonate solution
3. 3
   Dryingdried over sodium sulfate
4. 4
   workup.DISTILLATIONdistilled in a bulb tube

Procedure

A solution of 66.9 g (0.298 mol) of diethyl 5-hydroxypentylphosphonate, 32.6 g (0.38 mol) of 3,4-dihydropyran and 1 g (0.004 mol) of pyridinium toluene-4-sulfonate in 800 ml of dichloromethane was heated under reflux for 16 hours. The solution was washed with water and saturated sodium hydrogen carbonate solution, dried over sodium sulfate and distilled in a bulb tube.

Source