Silver-hydrogen-calcium system

Much early work [21] involved the use of silver(I) fluoride, conveniently prepared from the oxide or carbonate with 40% hydrogen fluoride, for the exchange of single halogen atoms in alkyl halides [22] and other systems [23]. The use of calcium fluoride as a solid, inert support may increase the reactivity of silver fluoride [24] (Figure 3.1). 

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