反应详情

温度

-78 °C

A cooled (−78° C.) solution of 2-bromo-1-ethoxy-3-fluorobenzene (3.520 g; 16.10 mmol) in anh. THF (60 ml), under nitrogen, was treated dropwise with a solution of 1.6 M n-BuLi in hexanes (10.05 ml; 16.10 mmol). The resulting solution was further stirred at −78° C. for 5 min. A solution of ethyl 4-((tert-butylsulfinyl)imino)-2-methylbutanoate (2.650 g; 10.70 mmol) in anh. THF (20 ml) was then added dropwise to the cooled reaction mixture, and stirring at −78° C. was continued for 30 min. The resulting reaction mixture was treated successively with aq. sat. NH4Cl (75 ml), Et2O (250 ml) and water (75 ml). The separated organic layer was then washed with brine (75 ml), dried over anh. MgSO4, filtered, and concentrated to dryness under reduced pressure. Purification by FC (DCM/MeOH=30/1) afforded ethyl 4-(1,1-dimethylethylsulfinamido)-4-(2-ethoxy-6-fluorophenyl)-2-methylbutanoate as a yellow oil. LC-MS (conditions A): tR=0.85 min. and [M+H]+: 388.35 g/mol; tR=0.88 min. and [M+H]+: 388.37 g/mol (mixture of diastereoisomers).

1. stirringstirring at −78° C.
2. waitwas continued for 30 min
3. customThe resulting reaction mixture
4. washThe separated organic layer was then washed with brine (75 ml)
5. dry with materialdried over anh. MgSO4
6. filtrationfiltered
7. concentrationconcentrated to dryness under reduced pressure
8. customPurification by FC (DCM/MeOH=30/1)