Pentafluorosulfanyl halides

It is reported that SF5C1 (m.p., -64°C b.p., -21°C) is stable up to ca. 400°C in inert vessels, but decomposes at substantially lower temperature in the presence of Cu/Hg or in ultraviolet light. It is not hydrolyzed by water or aqueous acids, but is rapidly decomposed by aqueous alkali (14)  

The bromo derivative, SF5Br (m.p., -78°C b.p., 31°C), is less stable thermally, with decomposition starting at 150°C. The products of the thermal decomposition of SF5X (X = Cl, Br) are SF6, SF4, and X2. The products of UV photolysis of SF5Br are SF6, SF4, S2F10, and Br2 15). The vacuum-UV photolysis of SF5Br in an Ar matrix at 8 K provides a convenient method of generating BrF 16). 

When SFgCl reacts with trimethylsilylcyanide, (CH3)3SiCN, at -10°C, a white sublimable solid, S(CN)2 (32), is formed. On reaction of SF5C1 with (CF3)2NCN under photolytic conditions, (CF3)2NC(C1)= NSF5 is obtained (33), and with (CF3)2NCF2N(C1)CF3, (CF3)2NCF2N-(SF5)CF3 is produced in 50% yield. This product is characterized by spectral (IR, NMR, mass) data (34). 

The reaction of LiN=C(CF3)2 with SF5X leads to stepwise replacement of fluorine with concomitant fluoride ion migration as shown (37-39)  

Both SF5C1 and SF5Br react with unsaturated organic compounds. There are numerous examples of the addition of an SF5 group and a halogen atom across a C=C, C=0, C=C, or C=N bond, although under certain conditions fluorination also occurs. The photochemical reactions of SF5C1 with olefins have been studied in detail and are believed to involve a chain reaction as shown below (40). 

The vapor-phase Raman spectrum of SF5CI (17), the argon-matrix Raman and infrared spectra of SF5CI and SFsBr (18), and the vapor-phase infrared and liquid-phase Raman spectra of SFsBr 19), as well as photoelectron diffraction 20) and microwave spectra of SF5CI 21) and SFjBr 22) have been reported. The ionization potential of SF5 (9.65 eV) has been measured by photoionization mass spectrometry of SF5CI (23). 

Under photochemical conditions SF5CI can be reacted with some simple substrates. For example, with H2 it gives S2F10 (27) with O2, the products are SF5OOSF5 and SF5OSF5 (28) and with N2F4, SF5NF2 is obtained (29). The ability of SFjX to form the stable SFg- radical is an important feature of its chemistry. 

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Pentafluorosulfanyl Af,N-difluoramine, 41 146 Ai-Pentafluorosulfanyl fluoroitnine, 41 154 Pentafluorosulfanyl halides, 41 126-130 N-Pentafluorosulfanyl haloimines, 41 152-154 Pentafluorosulfanyl hypohalites, 41 130-132 SF5OF, 41 130-131... 

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