反应详情

9.6 g of tert.-butyl (4S)-3-benzyloxycarbonyl-2-oxo-imidazolidine-4-carboxylate are dissolved in 200 ml of dimethylformamide, and 14.0 g of silver oxide are added thereto. 42.6 g of methyl iodide are added to the mixture at room temperature under stirring, and the mixture is further stirred for 2 days in the dark. The reaction mixture is filtered to remove insoluble materials, and the filtrate is condensed under reduced pressure. The residue obtained is dissolved in ethyl acetate. Then, the ethyl acetate solution is washed with water, dried and condensed under reduced pressure. The residue thus obtained is washed with n-hexane. 8.45 g of tert.-butyl (4S)-1-methyl-3-benzyloxycarbonyl-2-oxo-imidazolidine-4-carboxylate are thereby obtained as colorless crystals. Yield: 84.3% M.p. 102°-103° C.

1. stirringthe mixture is further stirred for 2 days in the dark
2. filtrationThe reaction mixture is filtered
3. customto remove insoluble materials
4. customcondensed under reduced pressure
5. customThe residue obtained
6. washThen, the ethyl acetate solution is washed with water
7. customdried
8. customcondensed under reduced pressure
9. customThe residue thus obtained
10. washis washed with n-hexane