反应详情

To a cooled (0° C.) solution of 2-(2-methoxy-4-trifluoromethyl-phenyl)-4,4-dimethyl-4,5-dihydro-oxazole (intermediate AG) (1.0 g, 3.66 mmol) in 6.0 ml THF, was added dropwise a 1M ispropylmagnesium bromide solution in THF (11.0 ml, 10.98 mmol) maintaining the temperature below 5° C. The mixture was allowed to warm to room temperature and stirred for 1 hour. The mixture was cooled in an ice bath and quenched dropwise with 25 ml saturated NH4Cl solution. Ethyl acetate was added. The organic layer was separated and the aqueous layer was reextracted once with ethyl acetate. The combined extracts were dried over Na2SO4, filtered and concentrated in vacuo. The crude oil was purified on silica gel (eluent: heptane/ethyl acetate 0 to 20%) to provide 0.95 g (91%) of the title compound as a light yellow oil. MS (m/e): 286.1 (M+H).

1. temperaturemaintaining the temperature below 5° C
2. temperatureThe mixture was cooled in an ice bath
3. customquenched dropwise with 25 ml saturated NH4Cl solution
4. additionEthyl acetate was added
5. customThe organic layer was separated
6. dry with materialThe combined extracts were dried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe crude oil was purified on silica gel (eluent: heptane/ethyl acetate 0 to 20%)