反应详情

To a stirred solution of 674 mg. (2.64 mmoles) of 4-hydroxy-2-(6-carbethoxyhexyl)cyclopent-2-en-1-one (Example 29) and 2.22 g. (26.4 mmoles) of dihydropyran in 2.6 ml. of methylene chloride is added 5.0 mg. (0.026 mmoles) of p-toluenesulfonic acid monohydrate. After stirring for 20 minutes at room temperature the solution is diluted with ether and poured into saturated sodium chloride solution containing a little sodium bicarbonate. The organic phase is separated and washed with saturated sodium chloride solution. The extract is dried over magnesium sulfate, and volatile matter is evaporated at reduced pressure to give an oil, λmax.MeOH =224 mμ (7950); νmax.=1735 (ester carbonyl group), 1710 (ketone carbonyl group), and 1030 cm-1 (tetrahydropyranyloxy group).

1. customThe organic phase is separated
2. washwashed with saturated sodium chloride solution
3. dry with materialThe extract is dried over magnesium sulfate, and volatile matter
4. customis evaporated at reduced pressure
5. customto give an oil, λmax