反应详情

To a solution of 4-bromo-3-ketobutyric acid diphenylmethyl ester (2b, 11.4 g, 32.8 millimoles) in methanol dried with Molecular Sieves is added sodium formate (3.40 g, 50.0 millimoles), and the mixture is refluxed for 4 hours. The reaction mixture is filtered to remove solid material concentrated under reduced pressure, and extracted with ethyl acetate. The extract is washed with water, dried over magnesium sulfate and evaporated to remove the solvent. The residue is purified by chromatography over Lobar® column B using a mixture of benzene and ethyl acetate (3:1) as eluting solvent to afford the title compound (3b, 4.39 g, 47%).

1. temperaturethe mixture is refluxed for 4 hours
2. filtrationThe reaction mixture is filtered
3. customto remove solid material
4. concentrationconcentrated under reduced pressure
5. extractionextracted with ethyl acetate
6. washThe extract is washed with water
7. dry with materialdried over magnesium sulfate
8. customevaporated
9. customto remove the solvent
10. customThe residue is purified by chromatography over Lobar® column B
11. additiona mixture of benzene and ethyl acetate (3:1)
12. washas eluting solvent