3,4-dihydro-2H-pyran → 2-Propanone, 1,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]-

Participants

Reaction Conditions

Reaction Steps

9 g of 2,5-dihydroxy-1,4-dioxane-2,5-dimethanol is introduced into 60 ml of dioxane and the suspension is taken to about 70° C. for 15 minutes then returned to ambient temperature. 20 ml of 3,4-dihydro 2H-pyran and 300 mg of monohydrated paratoluene sulphonic acid are then added and the temperature is maintained at about 40° C. then the whole is left for 16 hours at ambient temperature. The reaction medium is poured into a mixture of 300 ml of saturated sodium bicarbonate solution +10 ml of triethylamine and extraction is carried out 4 times with methylene chloride. The organic phase is washed with salt water and dried. After purification by passage through silica, eluting with cyclohexane-ethyl acetate: 8-2 with 0.5% of triethylamine, 17 g of expected product (pale yellow syrup) is obtained.

Provenance & Evidence