反应详情

A solution of 0.14 moles of methylmagnesium bromide in diethyl ether was prepared by dissolving 15.5 g of 3M methylmagnesium bromide solution (in diethyl ether) in 100 ml of specially dried diethyl ether. While stirring at 25°-30° , a solution of 25.8 g of 1,3-bis(2-tetrahydropyranyloxy)-2-propanone, prepared as above, in 100 ml of diethyl ether was added dropwise. A white solid separated and refluxing occurred. The mixture was warmed to maintain reflux for 1 hour, then allowed to stand for 16 hours. Saturated ammonium chloride solution (100 ml) was added very slowly and when addition was completed, the layers were separated. The aqueous layer was extracted (2 × 100 ml) with diethyl ether. The ether solutions were combined, washed (2 × 100 ml) with water and dried over magnesium sulfate. The dried solution was concentrated and distilled to give 16.2 g of 2-methyl-1,3-bis(2-tetrahydropyranyloxy)-2-propanol, b.p. 121°-136°/2--3 × 10- 4 mm.

1. additionwas added dropwise
2. customA white solid separated
3. temperaturerefluxing
4. temperatureThe mixture was warmed
5. temperatureto maintain
6. temperaturereflux for 1 hour
7. additionSaturated ammonium chloride solution (100 ml) was added very slowly
8. additionwhen addition
9. customthe layers were separated
10. extractionThe aqueous layer was extracted (2 × 100 ml) with diethyl ether
11. washwashed (2 × 100 ml) with water
12. dry with materialdried over magnesium sulfate
13. concentrationThe dried solution was concentrated
14. distillationdistilled