Reaction #67524

Reaction equation

3,4-Dihydro-2H-pyran

1

4-Bromo-1-butanol

→

product 2

Yield 92.3%

2-(4-Bromobutoxy)-tetrahydro-2H-pyran

Yield 92.3%

Solvents

dichloromethane

Conditions

Workup

1. 1
   OtherAfter removing the solvent
2. 2
   Otherthe residue was purified by flash chromatography on silica gel with 5:1 hexanes/ethyl acetate as the eluent

Procedure

3,4-Dihydro-2H-pyran (8.5 mL, 90.96 mmol) was added dropwise to the dichloromethane (20 mL) solution of 1 (10.7 g, 69.93 mmol) and p-toluenesulfonic acid monohydrate (26.5 mg, 0.1372 mmol). The mixture was stirred at room temperature over night. After removing the solvent, the residue was purified by flash chromatography on silica gel with 5:1 hexanes/ethyl acetate as the eluent to yield product 2 as a colorless oil (15.3 g, 92%). 1H NMR (400 MHz, CDCl3): δ 1.48-1.62 (m, 4H), 1.68-1.85 (m, 4H), 1.94-2.02 (m, 2H), 3.40-3.53 (m, 4H), 3.74-3.88 (m, 2H), 4.57-4.59 (m, 1H).

Source