Asymmetric fluoro-organomercurials. Part 2. The synthesis and characterisation of the fluorovinyl-mercurials RHgCXCF2 (R = Ph, Fc; X = F, Cl): The single crystal X-ray structures of PhHgCFCF2, FcHgCFCF2 and FcHgCClCF2[Fc(η5-C5H5)Fe(η5-C5H4-)]

The asymmetric fluorovinyl mercurials RHgCXCF2 (R = Ph, Fc; X = F, Cl) have been prepared from RHgCl and LiCXCF2, the later being derived from the reaction of HFC-134a, CF3CH2F (X = F) or HCFC-133a, CF3CH2Cl (X = Cl) and n-BuLi. All the complexes have been fully characterised by spectroscopic methods and, apart from PhHgCClCF2, the compounds are sufficiently stable to be investigated by single-crystal X-ray diffraction, making this the first report of structurally characterised asymmetric fluorovinyl mercurial complexes of the type RHg(CXCF2). In the solid state all of the structurally characterised complexes demonstrate asymmetric Hg–C distances and extensive intramolecular Hg⋯F and Hg⋯η2-arene interactions are observed.

Graphical abstractThe compounds RHgCXCF2 (R = Ph, Fc; X = F, Cl) have been prepared, in high yields, as the first fully characterised examples of asymmetric Hg(II) complexes of this type. The crystal structures of RHgCXCF2 reveal a series of short Hg⋯F and Hg⋯η2-arene interactions.Figure optionsDownload full-size imageDownload as PowerPoint slide