Polyfluorinated mercury thiolates. 199Hg NMR studies and the crystal structure of [Hg(SC6H4(CF3)-2)2]

We have studied a series of homoleptic polyfluorinated mercury thiolates, [Hg(SRF)2] (RF = C6F4(CF3)-4 1, C6F5 2, C6HF4-4 3, C6H4F-2 4, C6H4F-3 5, C6H4F-4 6, C6H4(CF3)-2 7, C6H4(CF3)-3 8, C6H4(CF3)-4 9, C6H4(OCF3)-4 10, C6H3F2-3,5 11 and C6H3(CF3)2-3,5 12) synthesized by methatetical reactions of the corresponding fluorinated thiols with mercury(II) acetate. The 199Hg NMR chemical shift data for this series of homoleptic Hg(II) complexes spans over the range from ca. −1300 up to ca. −1400 ppm. Upfield chemical shifts in these NMR spectra are seen for perfluorinated ligands and there seems to be a correlation between the number of fluorine atoms on the aromatic ring (or group electronegativity), their relative positions on the ring and the corresponding chemical shifts. We also report the X-ray diffraction crystal structure of the complex [Hg(SC6H4(CF3)-2)2] 7. The molecule crystallizes in the space group P−1 with an almost perfect linear coordination (SHgS 177.03(5)°) around the Hg(II) atom.