Autor: |
Alan W. Baker, William D. S. Scott, Irene Nicol, Scott John David, Watson Michael John, Geoffrey Webb, John M. Winfield, David William Bonniface, Ronald R. Spence, Thomas M. Klapötke |
Rok vydání: |
2000 |
Předmět: |
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Zdroj: |
Journal of Fluorine Chemistry. 102:279-284 |
ISSN: |
0022-1139 |
Popis: |
Catalytic fluorination of trichloroethene by anhydrous hydrogen fluoride at 653 K in the presence of fluorinated amorphous chromia under static conditions leads to a mixture of products in which partially halogenated olefins predominate. These are converted to mixtures containing CF3CH2F and CF3CH2Cl by a second fluorination using fresh catalyst. The results of product analyses from reactions carried out under various conditions have been used to design a synthesis of [18F]-CF3CH2F from CCl2CHCl. It is proposed that [18F] labelling occurs via direct [18F]- for [19F] exchange rather than by a dehydrofluorination/hydrofluorination route. [36Cl]-labelled CF3CH2Cl is readily prepared from CF3CH2F and H36Cl in the presence of chromia catalysts. Enthalpies of dehydrofluorination of CF3CH2F and CF3CH2Cl in the vapour phase have been computed. 1 |
Databáze: |
OpenAIRE |
Externí odkaz: |
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