CRYSTAL-STRUCTURE AND SOLID-STATE P-31 CP-MAS NMR-SPECTRUM OF THE BIS(TRIFLUOROACETATO) (TRIPHENYLPHOSPHINE)MERCURY(II) DIMER [HG(CF3CO2)2PPH3]2

The title compound belongs to the monoclinic space group P21/c, a=20.29(1), b=12.644(8), c=18.25(1), Å, β=95.76(5)°. The unit cell contains two dimeric [Hg(CF3CO2)2PPh3]2 molecules in which each Hg atom forms strong primary bonds to a PPh3 molecule and an oxygen of a monodentate trifluoroacetate ligand. These two Hg atoms are bridged by two extra trifluoroacetate ligands, one providing a single oxygen to a Hg-O-Hg bridge, the other including both carboxylate oxygens in a Hg-O-C-O-Hg bridging moiety. This unusual type of bridging makes the two halves of the molecule symmetry independent, leading to distinct signals at 31.5 and 29.9 ppm for the phosphines in the31P CP-MAS NMR spectrum of the solid complex. © 1990 Plenum Publishing Corporation.