反应详情

25 mmol 7-Hydroxy-2,2-dimethyl-benzofuran-3-one and 30 g silica gel are stirred in 200 ml chloroform. A solution of 25 mmol N-chloro-diisopropylamine in 100 ml chloroform (prepared from diisopropylamine and aqueous sodium hypochlorite solution, extracted in chloroform, concentration determined iodometrically) is added dropwise. After stirring for 10 hours it is filtered and the filtrate is shaken out with water. The solution is dried over sodium sulfate. The solvent is removed by distillation at 300 mbar. The residue is separated by column chromatography (silica gel: ethyl acetate).

1. extractionextracted in chloroform
2. concentrationconcentration determined iodometrically)
3. additionis added dropwise
4. filtrationis filtered
5. stirringthe filtrate is shaken out with water
6. dry with materialThe solution is dried over sodium sulfate
7. customThe solvent is removed by distillation at 300 mbar
8. customThe residue is separated by column chromatography (silica gel: ethyl acetate)