Polyfluoromonoiodoalkanes react photochemically with dimethyl sulphide to give as major products the corresponding methyl polyfluoroalkyl sulphides, the corresponding 1H-polyfluoroalkanes, 2,4-dithiapentane and trimethylsulphonium iodide. Thermal reaction of heptafluoro-1-iodopropane with dimethyl sulphide gives a higher yield of 1H-heptafluoropropane, at the expense of methyl heptafluoropropyl sulphide, than in the corresponding photochemical reaction. The products are explained on the basis of a free-radical mechanism.

AbstractDie Fluor‐jodalkane (I) reagieren photochemisch mit dem Sulfid (II) (14‐28 Tage) unter Bildung von Gemischen aus den Fluoralkyl‐methyl‐sulfiden (III) (32‐63% Ausbeute), den Polyfluoralkanen (IV) (33‐66%), dem Dithiapentan (V) (15‐53%) und dem Sulfoniumjodid (VI) (83‐9l%).

Methyl polyfluoroalkyl sulphides, synthesised by two novel routes: (i) photochemical reaction of a polyfluoroiodoalkane with dimethyl sulphide or dimethyl disulphide and (ii) reaction of a polyfluoroiodoalkane with sodium methanethiolate in the presence of dimethyl disulphide, are useful precursors of polyfluoroalkane-sulphonic acids.

AbstractDie Belichtung einer l:4‐Mischung aus den Perhalogenalkyl‐jodiden (Ia)‐(Ie) und Dimethylsulfid (II) ergibt die Methyl‐polyfluoralkyl‐sulfide (IIIa)‐(IIIe) in 32‐63%iger Ausbeute.