反应详情

A mixture of ether (14 ml) and 40% aqueous potassium hydroxide (4.2 ml) was cooled in ice. N-Nitrosomethylurea (1.4g) was added in portions with gentle swirling over 30 min. The ether layer was decanted and dried over solid potassium hydroxide for 15 min. The ether solution was decanted, then cooled in an ice bath. A solution of 2-methoxy-4-(1-acetyl-4-piperidyloxy)benzoyl chloride (0.58 g, 1.86 mmol) in THF (3 ml) was added dropwise and the mixture was stirred at ambient temperature for 2 hours. Nitrogen was passed through the mixture for 1 hour, and the solution was then concentrated in vacuo. The residue was dissolved in methanol and treated with freshly prepared silver oxide (48 mg), and the mixture was heated at reflux for 30 min. Three additional lots of 100 mg of silver oxide were added with 1 hour reflux following each. The mixture was cooled and filtered, and the filtrate was concentrated in vacuo. The residue was chromatographed on silica gel eluted with 2%, followed by 4% methanol in methylene chloride. The product fractions were combined and evaporated to dryness in vacuo to give methyl 2-methoxy-4-(1-acetyl-4-piperidyloxy)phenylacetate.

1. temperaturewas cooled in ice
2. customThe ether layer was decanted
3. dry with materialdried over solid potassium hydroxide for 15 min
4. customThe ether solution was decanted
5. temperaturecooled in an ice bath
6. waitNitrogen was passed through the mixture for 1 hour
7. concentrationthe solution was then concentrated in vacuo
8. dissolutionThe residue was dissolved in methanol
9. additiontreated with freshly prepared silver oxide (48 mg)
10. temperaturethe mixture was heated
11. temperatureat reflux for 30 min
12. additionThree additional lots of 100 mg of silver oxide were added with 1 hour
13. temperaturereflux
14. temperatureThe mixture was cooled
15. filtrationfiltered
16. concentrationthe filtrate was concentrated in vacuo
17. customThe residue was chromatographed on silica gel
18. washeluted with 2%
19. customevaporated to dryness in vacuo