反应详情

A solution of 0.30 g (0.81 mmol) (4R,9aR)-6-bromo-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester in 20 ml diethyl ether was cooled to −100 deg C. and treated dropwise with 65 μl (0.97 mmol) tert-butyllithium (1.5 M solution in n-pentane). After 15 min, 0.12 g (0.11 ml, 0.98 mmol) 5-chloro-2-pentanone was added, the temperature was allowed to rise to −75 deg C. and after an additional 15 min, the reaction was quenched with 10%. aqueous ammonium chloride solution and extracted with ethyl acetate. The organic layer was washed with brine, dried over magnesium sulfate and filtered. The solvent was removed on a rotary evaporator and the residue was chromatographed on silica gel (0.032–0.063 mm) with ethyl acetate:n-hexane (1:2) as eluant to afford the compound as a colorless oil (50.9%).

1. customto rise to −75 deg C
2. waitand after an additional 15 min
3. customthe reaction was quenched with 10%
4. extractionaqueous ammonium chloride solution and extracted with ethyl acetate
5. washThe organic layer was washed with brine
6. dry with materialdried over magnesium sulfate
7. filtrationfiltered
8. customThe solvent was removed on a rotary evaporator
9. customthe residue was chromatographed on silica gel (0.032–0.063 mm) with ethyl acetate:n-hexane (1:2) as eluant