p-Toluenesulfonic acid → 2-(2-Bromoethoxy)tetrahydro-2H-pyran

Participants

Reaction Steps

2.29 ml of 2-bromoethanol was dissolved in 27.8 ml of dry dichrolomethane, and 7.21 ml of dihydropyran and then 48.1 mg of dry p-toluenesulfonic acid were added thereto. The mixture was stirred at room temperature for 3 hours. Then, the reaction mixture was partitioned with 150 ml of chloroform and 75 ml of a 4% sodium hydrogen-carbonate aqueous solution. The organic layer was washed sequentially with water and a saturated sodium chloride aqueous solution and then dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (50 g of Kieselgel 60) by using a mixture of hexane/ethyl acetate (20/1). The product-containing fractions were put together, and the solvent was distilled off under reduced pressure to obtain 5.4 g of 2-bromo-1-(2-tetrahydropyranyloxy)ethane as a oily substance.

Provenance & Evidence