反应详情

温度

-50 °C

To a solution of 3.5 mL of DIPA in 6 mL THF were added dropwise 9.9 mL of n-butyllithium (2.5M in Hept) at −20° C. After 20 min, 12 mL of toluene were added and the solution was stirred for 30 min. The mixture was cooled to −50° C., 4.5 mL of tert.-butyl acetate were added and stirring was continued for 1 h at −50° C. Then, 2.5 g of rac-(1R*,8R*)-tricyclo[6.2.2.02,7]dodeca-2,4,6-trien-9-one dissolved in 6 mL of toluol were added and the solution was stirred at −50 to −20° C. over 2.5 h. The reaction mixture was poured on ice/aq. HCl, the organic phase was separated, washed with sat. aq. NaHCO3, dried over Na2SO4 and concentrated in vacuo. The crude reaction product was purified by CC with Hept/EtOAc (4:1) to yield 2.6 g of the major racemate, rac-(1R*,8R*,9R*)-(9-hydroxy-tricyclo[6.2.2.02,7]dodeca-2,4,6-trien-9-yl)-acetic acid tert-butyl ester as beige solid and 0.4 g of the minor racemate, rac-(1R*,8R*,9S*)-(9-hydroxy-tricyclo[6.2.2.02,7]dodeca-2,4,6-trien-9-yl)-acetic acid tert-butyl ester as yellow oil.

1. stirringstirring
2. waitwas continued for 1 h at −50° C
3. additionwere added
4. stirringthe solution was stirred at −50 to −20° C. over 2.5 h
5. additionThe reaction mixture was poured on ice/aq
6. customHCl, the organic phase was separated
7. washwashed with sat. aq. NaHCO3
8. dry with materialdried over Na2SO4
9. concentrationconcentrated in vacuo
10. customThe crude reaction product
11. customwas purified by CC with Hept/EtOAc (4:1)