Radiotracers in fluorine chemistry. Fluorine-18 exchange between Group I fluorides and trifluoroacetyl fluoride or sulphur tetrafluoride. The effect of Group I fluorides on chlorine-36 exchange between chloride and sulphur chloride pentafluoride

Abstract

Fluorine-18 exchange has been observed between Group I fluorides (Cs–Li inclusive) and trifluoroacetyl fluoride or sulphur tetrafluoride at 150 and 50°C. In all cases the order of exchange observed is Cs > Rb > K > Na > Li. Chlorine-36 exchange between chlorine and sulphur chloride pentafluoride at 150°C is enhanced by the presence of Group I fluorides. The order of enhancement parallels the order of fluorine-18 exchange ability. The results are discussed in relation to the formation of the anions C₂F₅O- and SF₅^–.