To a solution of 2-(tert-butyldimethylsilanyloxy)-1-phenylethanol (0.73 g, 2.9 mmol) and 3,4-dihydro-2H pyran (486 mg, 5.78 mmol) in dichloromethane (30 ml) was added p-toluenesulfonic acid monohydrate (50 mg). The mixture was stirred at room temperature for 12 hours and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (eluent; hexane/ethyl acetate=3/1) to give tert-butyldimethyl[2-phenyl-2-(tetrahydropyran-2-yl-oxy)ethoxy]silane (0.86 g, 2.9 mmol, >99%) as a colorless oil.
