反应详情

A portion of the title compound from Example 77 (395.1 mg; 1.5 mmol) was dissolved in 9 ml of methanol. Magnesium (72.9 mg; 3.0 mmol) was then added to the solution and the resulting reaction mixture was stirred at room temperature for 3 hours. After 3 hours, most of the magnesium which had been added originally appeared to be gone so an additional 182.3 mg (7.5 mmol) of magnesium were added. Stirring of the reaction solution at room temperature continued overnight. By the next morning a yellow precipitate had formed. This precipitate was dissolved by adding the methanolic reaction solution to an ethyl acetate/1N hydrochloric acid mixture. The organic layer from the resulting two-phase mixture was isolated and then dried over sodium sulfate. The volatile components of the organic layer were removed and the resulting residue was chased with methylene chloride. The residue was then dissolved in 25 ml of methylene chloride and the resulting solution was chromatographed on a silica gel chromatography column using a 5-20% isopropyl alcohol in hexanes gradient. Those fractions identified as containing essentially pure product were evaporated to provide 0.29 g of title compound. m.p. 65°-70° C.

1. customthe resulting reaction mixture
2. waitAfter 3 hours
3. additionwere added
4. stirringStirring of the reaction solution at room temperature
5. waitcontinued overnight
6. customBy the next morning a yellow precipitate had formed
7. dissolutionThis precipitate was dissolved
8. customThe organic layer from the resulting two-phase mixture was isolated
9. dry with materialdried over sodium sulfate
10. customThe volatile components of the organic layer were removed
11. dissolutionThe residue was then dissolved in 25 ml of methylene chloride
12. customthe resulting solution was chromatographed on a silica gel chromatography column
13. additionas containing essentially pure product
14. customwere evaporated