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

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.

1. customThen, the reaction mixture was partitioned with 150 ml of chloroform and 75 ml of a 4% sodium hydrogen-carbonate aqueous solution
2. washThe organic layer was washed sequentially with water
3. dry with materiala saturated sodium chloride aqueous solution and then dried over anhydrous sodium sulfate
4. distillationThe solvent was distilled off under reduced pressure
5. customthe residue was purified by silica gel column chromatography (50 g of Kieselgel 60)
6. additiona mixture of hexane/ethyl acetate (20/1)
7. distillationthe solvent was distilled off under reduced pressure

ORD record

ord-13efcb7b3ecd4efbb2132fe34702eb57

Source dataset

uspto-grants-1989_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04851387