反应详情

To a suspension of 15.8 g of sodium hydride (dispersion in oil) in 500 ml of tetrahydrofuran are added dropwise 67 g (300 mMol) of ethyl 1,1-diethoxyethylphosphinate at such a rate so that the temperature does not exceed 25° C. This mixture is stirred for one hour at room temperature, then cooled to -10° C. and 77.8 g (900 mMol) of chlorodifluoromethane are introduced. Stirring is continued for another 2 hours at room temperature, then 100 ml of ice-cold water are added. The mixture is extracted three times with dichloromethane and the combined extracts dried over magnesium sulphate. Removal of the solvent in vacuo gives ethyl 1,1-diethoxyethyl(difluoromethyl)phosphinate as a viscous oil,Rf=0.44 (CH2Cl2 /CH3COOH, 9+1).

1. customdoes not exceed 25° C
2. temperaturecooled to -10° C.
3. stirringStirring
4. waitis continued for another 2 hours at room temperature
5. extractionThe mixture is extracted three times with dichloromethane
6. dry with materialthe combined extracts dried over magnesium sulphate
7. customRemoval of the solvent in vacuo