GB452656A - Process for the manufacture of organic compounds containing fluorine - Google Patents

Abstract

<PICT:0452656/IV/1> Organic compounds containing fluorine are prepared in good yield and in a smooth manner by allowing fluorine which is substantially free from oxygen and oxides of fluorine to react in a finely distributed state upon the organic compounds. Fluorine of the required degree of purity can be prepared by electrolyzing a melt of potassium bifluoride which is substantially free from water, preferably having a water content below 0,05 per cent. The distribution of the fluorine is effected by the use of solid filling materials such as iron, copper, silver and cerium arranged in the form of coils, wire nets, sponges, grains, &c. Two forms of apparatus are described which effect a fine distribution of the fluorine and allow the materials to interact in small gas spaces. For example, in apparatus as shown, the liquid to be fluorinated enters through valve n into the reaction chamber k filled with packing material. Fluorine enters through ducts s and inlet tubes i provided with bore holes and surrounded by packings r of inert material. The reaction product is drawn off at v. It is preferred to conduct the reaction in the gaseous phase, but in the case of difficulty volatile materials the reaction can be conducted in solution in an inert solvent such as carbon tetrachloride. In examples: (1) this example shows that carbon tetrachloride is inert to fluorine under the conditions of the invention, whereas under ordinary conditions it reacts with explosion; (2) fluorine is introduced into a -a -diphenylethylene to yield a -a -diphenyl-a -b -difluoroethylene in an amount equivalent to 85 per cent of the theoretical; (3) fluorine is passed into petroleum to give a product having a fluorine content of 9,8 per cent which represents a yield of 95 per cent; (4) fluorine is passed into a solution of cumarin in carbon tetrachloride to give a product having a fluorine content of 19,5 per cent.