反应详情

温度

30 °C

A solution of 22.9 g of 2-(p-bromophenyl)-1,3-dioxolan in 100 ml of tetrahydrofuran is added dropwise, at 60° C, to a well stirred suspension of 2.65 g of magnesium chips, which have been washed with chloroform and activated with iodine, in 100 ml of absolute tetrahydrofuran. The dropwise addition is carried out in such a manner that after the onset of the reaction, the temperature does not rise above 60° C. At the conclusion, the reaction mixture is heated for one hour, then cooled to 30° C and, while stirring, 11 g of cyclohexanone are added dropwise. After being heated for 1 hour to 50° C, the reaction mixture is evaporated in vacuo in a rotary evaporator and the residue mixed with ice and a saturated ammonium chloride solution. Extraction with ether is effected, and the ethereal extracts are dried over sodium sulphate and evaporated. The residue is distilled under a high vacuum and yields the 2-[p-(1-hydroxy-cyclohexyl)-phenyl]-1,3-dioxolan having a boiling point of 160°-170° C (0.05 mm Hg), which becomes solid on standing and melts at 95°-97° C after recrystallization from ether + petroleum ether.

1. washhave been washed with chloroform
2. additionThe dropwise addition
3. customafter the onset of the reaction
4. customdoes not rise above 60° C
5. temperatureAt the conclusion, the reaction mixture is heated for one hour
6. stirringwhile stirring
7. temperatureAfter being heated for 1 hour to 50° C
8. customthe reaction mixture is evaporated in vacuo in a rotary evaporator
9. additionthe residue mixed with ice
10. extractionExtraction with ether
11. dry with materialthe ethereal extracts are dried over sodium sulphate
12. customevaporated
13. distillationThe residue is distilled under a high vacuum