反应详情

A solution of 4.3 g of 4-(3,5-difluorophenoxy)phenol and 1.58 g of pyridine or 2.58 g of ethyl diisopropylamine in 35 ml of dry dimethyl sulfoxide is metered at a constant rate at +25° C. in the course of 5 hours to a solution of 6.4 g of ethyl N-phenylthio-2-methylsulfonyloxyethylcarbamate and 0.2 g of hydroquinone in 20 ml of anhydrous dimethyl sulfoxide, with stirring. The mixture is stirred for 5 more hours at room temperature. After this, the reaction mixture is poured into ice-water and extracted three times with an ether/hexane mixture (1:4), and the combined organic phases are washed with water and dried over sodium sulfate. After the solvents have been distilled off in vacuo, the crude product is purified by chromatography, by which process ethyl N-phenylthio-2-[4-(3,5-difluorophenoxy)phenoxy]ethylcarbamate is isolated, nD20 1.5700.

1. stirringThe mixture is stirred for 5 more hours at room temperature
2. extractionextracted three times with an ether/hexane mixture (1:4)
3. washthe combined organic phases are washed with water
4. dry with materialdried over sodium sulfate
5. distillationAfter the solvents have been distilled off in vacuo
6. customthe crude product is purified by chromatography, by which process ethyl N-phenylthio-2-[4-(3,5-difluorophenoxy)phenoxy]ethylcarbamate
7. customis isolated