Explored routes to unknown polyfluoroorganyliodine hexafluorides, RFIF6

Two routes to RFIF6 compounds were investigated: (a) the substitution of F by RF in IF7 and (b) the fluorine addition to iodine in RFIF4 precursors. For route (a) the reagents C6F5SiMe3, C6F5SiF3, [NMe4][C6F5SiF4], C6F5BF2, and 1,4-C6F4(BF2)2 were tested. C6F5IF4 and CF3CH2IF4 were used in route (b) and treated with the fluoro-oxidizers IF7, [O2][SbF6]/KF, and K2[NiF6]/KF. The observed sidestep reactions in case of routes (a) and (b) are discussed. Interaction of C6F5SiX3 (X = Me, F), C6F5BF2, 1,4-C6F4(BF2)2 with IF7 gave exclusively the corresponding ring fluorination products, perfluorinated cyclohexadiene and cyclohexene derivatives, whereas [NMe4][C6F5SiF4] and IF7 formed mixtures of C6FnIF4 and C6FnH compounds (n = 7 and 9). CF3CH2IF4 was not reactive towards the fluoro-oxidizer IF7, whereas C6F5IF4 formed C6FnIF4 compounds (n = 7 and 9). C6F5IF4 and CF3CH2IF4 were inert towards [O2][SbF6] in anhydrous HF. CF3CH2IF4 underwent C–H fluorination and C–I bond cleavage when treated with K2[NiF6]/KF in HF. The fluorine addition property of IF7 was independently demonstrated in case of perfluorohexenes. C4F9CFCF2 and IF7 underwent oxidative fluorine addition at −30 °C, and the isomers (CF3)2CFCFCFCF3 (cis and trans) formed very slowly perfluoroisohexanes even at 25 °C. The compatibility of IF7 and selected organic solvents was investigated. The polyfluoroalkanes CF3CH2CHF2 (PFP), CF3CH2CF2CH3 (PFB), and C4F9Br are inert towards iodine heptafluoride at 25 °C while CF3CH2Br was slowly converted to CF3CH2F. Especially PFP and PFB are new suitable organic solvents for IF7.