反应详情

温度

2 °C

α-Cyclohexylstyrene was prepared from cyclohexyl phenyl ketone using standard Wittig chemistry (Gupta, P.; Fernandes, R. A.; Kumar, P. Tet. Lett. 2003, 44, 4231–4232.) Methyltriphenylphosphonium bromide (29.57 g, 82.77 mmol) was slurried in 600 mL THF in the glovebox. The mixture was cooled to 2° C., and nBuLi (1.6 M in hexanes, 52 mL) was added over 15 min. After 1 h, solid cyclohexyl phenyl ketone (15.18 g, 80.63 mmol) was added, and the solution was allowed to slowly warm to room temperature overnight. Water (200 mL) was added. The solution was extracted with Et2O (3×150 mL). The combined organic extracts were washed with brine, dried (MgSO4) and evaporated under vacuum to give a tan liquid. Ph3PO crystallized upon standing and was removed by filtration and washed with hexane (200 mL). The hexane solution was filtered through a 2 in column of neutral alumina, washing with an additional 200 mL of hexane. The filtrate was evaporated to a colorless liquid which was distilled (46–49° C./0.1 mm Hg) to give 13.72 g of colorless liquid (89% yield).

1. temperatureto slowly warm to room temperature overnight
2. extractionThe solution was extracted with Et2O (3×150 mL)
3. washThe combined organic extracts were washed with brine
4. dry with materialdried (MgSO4)
5. customevaporated under vacuum
6. customto give a tan liquid
7. customPh3PO crystallized
8. customwas removed by filtration
9. washwashed with hexane (200 mL)
10. filtrationThe hexane solution was filtered through a 2 in column of neutral alumina
11. washwashing with an additional 200 mL of hexane
12. customThe filtrate was evaporated to a colorless liquid which
13. distillationwas distilled (46–49° C./0.1 mm Hg)