423-62-1Relevant articles and documents
PROCESS FOR PRODUCING FLUOROALKYL IODIDE TELOMER
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Page/Page column 3-4, (2011/02/25)
A novel process for producing a fluoroalkyl iodide telomer is provided, which is able to obtain a fluoroalkyl iodide telomer having a desired chain length, efficiently. A fluoroalkyl iodide represented by the general formula RfI (wherein Rf is a C1-10 fluoroalkyl group) and tetrafluoroethylene are used as a telogen and a taxogen, respectively. These compounds are supplied to a distillation apparatus. In a reaction zone located in an intermediate part of the distillation apparatus, the compounds are subjected to a telomerization reaction in the presence of a metal catalyst with heating to generate a fluoroalkyl iodide telomer represented by the general formula Rf(CF2CF2)nI (wherein Rf is the same as defined above and n is an integer of 1-4). Thereafter, a fraction comprising the fluoroalkyl iodide telomer is separated by distillation.
METHOD FOR CONTINUOUS PRODUCTION OF A PERFLUOROALKYL IODIDE TELOMER
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Page 6, (2008/06/13)
The present invention relates to a process for continuously producing a perfluoroalkyl iodide represented by the general formula Rf(CF2CF2)nI, wherein Rf is a C1-6 perfluoroalkyl and n is an integer from 1 to 4, the method comprising continuously supplying a perfluoroalkyl iodide as a telogen represented by the general formula RfI, wherein Rf is as defined above, and tetrafluoroethylene as a taxogen to a tubular reactor packed with a metal catalyst comprising a powdery spherical metal or a sintered metal; and conducting telomerization at a temperature of 60 to 160°C under a pressure of 0.1 to 5 MPa (gauge pressure). According to the present invention, medium-chain perfluoroalkyl iodides can be continuously and efficiently produced with little generation of impurities, such as hydrogen-containing organic compounds and the like.
Highly selective photochemical synthesis of perfluoroalkyl bromides and iodides
Zhang,Zhang,Yang,Wang,Fuss,Weizbauer
, p. 153 - 168 (2007/10/03)
Highly fluorinated alkyl iodides are conveniently synthesized by telomerization of a fluoroalkyl-iodide, RI, with, e.g., C2F4. Normally, the reaction, often carried out in the liquid phase with a radical initiator, gives products with a broad distribution of molecular weights. In this work, we report a method that obtains selectively products of a desired molecular weight: this method is a photochemically induced reaction in the gas phase; the gas is circulated through a trap or a rectification still which continuously removes the heavier products, whereas the more volatile molecules return to the photoreactor. An analysis by rate equations shows which control parameters are important, and by a suitable choice of these parameters, we obtained a better selectivity for, e.g., C8F17I than previously. This method also works with BrC2F4Br instead of an iodide. In this case, we demonstrated in a small laboratory setup with simple low-pressure Hg lamps (5 × 30 W), a productivity of more than 0.5 kg/day. In the telomerization of CF3Br or HC2F4Br with C2F4 we found, however, a few percent of dibromide side products which are sometimes difficult to separate because of similar boiling points. For this case, it is better to synthesize the iodides instead, and then exchange the I for Br, if desired.
