Phosphorus oxydichlorofluoride preparation

Di 2 fluoroethyl phosphorofluoridate (XVIII) was prepared with the idea of combining the toxic principles of the fluoro-aoetates and of the phosphorofluoridates. It was readily obtained by the action of phosphorus oxydichlorofluoride on... 

Preparation of Esters of Phosphorofluoridic Acid by means of Phosphorus Oxydichlorofluoride... 

The method depended upon the availability of phosphorus oxydichlorofluoride, a compound described by Booth and Dutton,2 who devised an elaborate apparatus for the preparation of the compound in a pure condition for physicochemical measurements. We modified their process to suit the particular needs of this work. The generator which we developed for this step-... 

In order to determine whether other secondary alcohols would give phosphorofluoridic esters of high potency, dicycio-hexyl phosphorofluoridate (VIII) was prepared by the action of phosphorus oxydichlorofluoride on cyciohexanol. In this preparation it was essential to remove all the hydrogen chloride before distillation, otherwise decomposition took place. The... 

Diphenyl phosphorofluoridate was prepared in 60 per cent yield by the action of phosphorus oxydichlorofluoride on phenol in the presence of dimethylaniline to take up the hydrogen chloride formed. Gottlieb3 claimed to have prepared this... 

It should be emphasized that the phosphorus oxydichlorofluoride method for preparing esters of phosphorofluoridic acid cannot compare in speed with the hydrogen phosphite method already described (p. 46). Furthermore, it is not very suitable for very large-scale work. On the other hand, once the apparatus is set up and a supply of POCl2F is obtained, one has a simple, clear-cut, method for producing a large variety of phosphorus compounds, not only esters but amino compounds (p. 87) and mixed compounds (p. 90). In other words, the method is extremely valuable for exploratory purposes and where an unequivocal synthesis is required. 

Later, American workers2 described the preparation of this type of compound by a method which necessitated the loss of two-thirds of the fluorine concerned in the reaction. They prepared tetramethylphosphorodiamidic fluoride (bisdimethyl-aminofluorophosphine oxide) (II) by the action of phosphorus oxyfluoride on the calculated quantity of dimethylamine. In addition, it should be emphasized that phosphorus oxyfluoride is a gas and is more difficult than the liquid phosphorus oxydichlorofluoride to manipulate. In Report no. 14 on fluoro-phosphonates to the Ministry of Supply3 it was shown that our reaction could also be applied to the preparation of tetramethyl-... 

Although the action of POClaF on an alcohol cannot compete with the hydrogen phosphite method for large-scale work, the (vmer was found extremely valuable for exploratory purposes. In particular, it was found possible to prepare diaryl phosphoro-fluoridates (e.g. (C,H50)aPOF) and diethyl phosphorofluorido-dithiolate (diethyl dithiofluorophosphonate, (CaH5S)aPOF) by the action of phosphorus oxydichlorofluoride on the appropriate phenol or mercaptan. 

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