Reaction #6690

Reaction equation

4-bromobutan-1-ol

3,4-dihydropyran

potassium carbonate

→

2-(4-bromobutoxy)-tetrahydropyran

2-(4-Bromobutoxy)-tetrahydropyran

Solvents

dichloromethane

phosphorus oxychloride

Conditions

Workup

1. 1
   workup.STIRRINGthe reaction mixture was stirred at room temperature for 1 h
2. 2
   Otherquenched with water
3. 3
   Extractionextracted with dichloromethane
4. 4
   Washwashed with brine
5. 5
   Dryingdried over MgSO4
6. 6
   Concentrationconcentrated in vacuo
7. 7
   OtherPurification by chromatography on silica gel (5% EtOAc/hexanes)

Procedure

To a solution of commercially available 4-bromobutan-1-ol (16) (1 equi.) and 3,4-dihydropyran (17) (1.5 equi.) in dichloromethane (3 mL/mmole), phosphorus oxychloride (0.01 equi.) was added at room temperature. The reaction mixture was stirred at that temperature for 24 h. Then potassium carbonate (1 equi.) was added to the reaction mixture and the reaction mixture was stirred at room temperature for 1 h, quenched with water, extracted with dichloromethane, washed with brine, dried over MgSO4, and concentrated in vacuo. Purification by chromatography on silica gel (5% EtOAc/hexanes) afforded 2-(4-bromobutoxy)-tetrahydropyran (18), as a colorless oil (88%).

Source