反应详情

N,N-Dimethylformamide (10 ml) was cooled to 1 deg C. and treated dropwise with 5.1 ml (56.0 mmol) phosphorus oxychloride. After the addition the temperature was again cooled to 1 deg C. and a solution of 1.0 g (3.11 mmol) (R)-6-chloro-4-methyl-3,4-dihydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester in (Example 2, intermediate a) in 10 ml N,N-dimethylformamide was added. The cooling bath was removed and after 1.5 h at room temperature the reaction mixture was poured into saturated aqueous sodium bicarbonate solution and was extracted three times with ethyl acetate. The combined organic phases were washed with water and brine, dried over magnesium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel (0.032–0.063 mm) with ethyl acetate:n-hexane (1:3) as eluant to yield the desired compound as a yellow foam (55.2%).

1. additionAfter the addition the temperature
2. temperaturewas again cooled to 1 deg C
3. customThe cooling bath was removed and after 1.5 h at room temperature the reaction mixture
4. additionwas poured into saturated aqueous sodium bicarbonate solution
5. extractionwas extracted three times with ethyl acetate
6. washThe combined organic phases were washed with water and brine
7. dry with materialdried over magnesium sulfate
8. filtrationfiltered
9. customevaporated
10. customThe residue was purified by chromatography on silica gel (0.032–0.063 mm) with ethyl acetate:n-hexane (1:3) as eluant