反应详情

温度

50 °C

To a solution of the compound of step 4 (1.40 g, 2.33 mmol) in 15.5 ml of dioxane was added 3.5 ml of a 1 M aqueous solution of lithium hydroxide and the mixture was heated at 50° C. for 1 h. The solvents were evaporated under reduced pressure and the residue was dissolved in 45 ml of water. The solution was cooled to 0° C. and acidified to pH 2 with 5 N hydrochloric acid. The obtained suspension was extracted with EA and the combined organic phases were washed with brine, dried over sodium sulfate, filtered and evaporated to dryness. 1.37 g of the title compound were obtained as a green solid melting at 103-105° C.

1. customThe solvents were evaporated under reduced pressure
2. dissolutionthe residue was dissolved in 45 ml of water
3. temperatureThe solution was cooled to 0° C.
4. extractionThe obtained suspension was extracted with EA
5. washthe combined organic phases were washed with brine
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. customevaporated to dryness