A Novel Method for Constructing a CF₂ Group via the Reaction of Alkynes with BrF and IF Prepared Directly from the Corresponding Elements

The molecules of IF and BrF as entities, prepared from the respective elements, have practically never been used in organic chemistry. When reacted with various types of alkynes the unknown family of compounds containing CF₂CX₂ (X = I, Br) was obtained in good yields. With phenylacetylenes an additional substitution of one or both X atoms by fluorine was observed. Very deactivated triple bonds, such as 23 and 25, react successfully only with BrF. Since the starting material is F₂ and most reactions are fast, this method should be suitable for synthesis of biologically interesting ¹⁸F-containing compounds. The main method used previously for introducing the elements of XF into organic molecules, namely with N-halo amides-anhydrous HF, is not suitable for reaction with alkynes.