反应详情

17.91 g of 2-hydroxyethyl 4-hydroxyphenyl sulfide prepared by the above process (1) was dissolved in 280 ml of tetrahydrofuran. 0.18 g of p-toluenesulfonic acid was added to the solution. A solution of 17.69 g of 3,4-dihydro-2H-pyran in 140 ml of tetrahydrofuran was added dropwise to the mixture under cooling with ice and then the mixture was stirred at room temperature for 4 h. The solvent was distilled off and the residue was extracted with diethyl ether, washed with an aqueous sodium hydrocarbonate solution and dried over anhydrous magnesium sulfate. The resulting solution was filtered and the filtrate was concentrated and subjected to silica gel column chromatography to obtain 15.38 g (yield: 58%) of the intended compound having the following physical properties:

1. temperatureunder cooling with ice
2. distillationThe solvent was distilled off
3. extractionthe residue was extracted with diethyl ether
4. washwashed with an aqueous sodium hydrocarbonate solution
5. dry with materialdried over anhydrous magnesium sulfate
6. filtrationThe resulting solution was filtered
7. concentrationthe filtrate was concentrated