128685-32-5Relevant academic research and scientific papers
Preparation of (Perfluoroalkyl)halogeno-1,3-diselenetanes from the Corresponding Selenocarbonyl Fluorides and Reactions with Boron Trichloride or Arsenic Pentafluoride
Boese, Roland,Haas, Alois,Spehr, Michael
, p. 51 - 61 (2007/10/02)
Reactions of Hg(SeRf)2 (Rf = C2F5, C3F7, CF3) with (C2H5)2AlI or AlI3 in octamethylcyclotetrasiloxane produce the unstable perfluoroalkaneselenocarbonyl fluorides 1 1 = CF3 (1a), C2F5 (1b), CF3Se (1c)>.These compounds are very reactive and polymerize to rubberlike products.On heating the polymers decompose almost quantitatively to the monomers or dimers.In CFCl3 solution 1 dimerizes at 20 deg C in sunlight to the corresponding cis/trans-1,3-diselenetanes 2.The structure of 2b is determined by single crystal X-ray diffraction.Different selenocarbonyl derivatives add to unsymmetrically substituted 1,3-diselenetanes 3. 1a and 1b react with cyclopentadiene to form the cycloaddition products 4a and 4c.Halogen exchange reactions take place between 2a-d and BCl3.The cis-isomers react much faster than the trans-isomers to give a mixture of cis-,trans-forms of 5.When 2c,d is treated with BCl3 it is possible to isolate and characterize the pure trans-isomer 2d, which is separated by preparative gas chromatography from 5c,d.Fluorine abstraction with formation of 1,3-diselenetan-2-ylium ions (6a-f) are accomplished by reactions of 2 or 3 with AsF5 in SO2.
