反应详情

To a stirred solution of 2.9 g (4.6 mmol) 2-methyl-butyric acid 8-[6-benzylcarbamoyl-5-(tert.-butyl-dimethyl-silanyloxy)-3-hydroxy-hexyl]-3,7-dimethyl-1,2,3,7,8,8a-hexahydro-naphthalen-1-yl ester and 5.2 ml (37 mmol) triethyl amine in 22 ml DMSO is added a solution of 4.4 g (28 mmol) SO3.pyridine complex in 22 ml DMSO. After 2 hours at room temperature the mixture is poured on ice and extracted twice with ethyl acetate. The combined organic phases are dried over sodium sulfate and the solvent evaporated. The residue is chromatographed over silica gel (hexane/ethyl acetate 9/1 to 7/3) to afford 2-methyl-butyric acid 8-[6-benzylcarbamoyl-5-(tert.-butyl-dimethyl-silanyloxy)-3-oxo-hexyl]-3,7-dimethyl-1,2,3,7,8,8a-hexahydro-naphthalen-1-yl ester as an oil. MS (FAB) m/z 630 ([M+Li]+).

1. additionAfter 2 hours at room temperature the mixture is poured on ice
2. extractionextracted twice with ethyl acetate
3. dry with materialThe combined organic phases are dried over sodium sulfate
4. customthe solvent evaporated
5. customThe residue is chromatographed over silica gel (hexane/ethyl acetate 9/1 to 7/3)