Synthesis and Structural Studies of Complexes of Bis(pentafluorophenyl)mercury with Di(phosphane oxide) Ligands

The reaction of bis(pentafluorophenyl)mercury with the ligands bis(diphenylphosphano) methane P,P'-dioxide ({Ph2P(O)}(2)CH2) (1), bis{2-(N,N,N'N'-tetraethyldiaminophosphano) imidazol-1-yl} methane P,P'-dioxide ({2-PO(NEt2)(2)C3N2H2}(2)CH2) (2) and bis (2-diphenylphosphanophenyl) ether P,P'-dioxide ({2-PPh2(O)C6H4}(2)O) (3) afforded crystalline sigma-donor complexes [{Hg(C6F5)(2)}(2){Ph2P(O)}(2)CH2] (1Hg), [Hg(C6F5)(2){2-PO(NEt2)(2)C3N2H2}(2)CH2](n) (2Hg) and [Hg(C6F5)(2){2-PPh2(O)C6H4}(2)O] (3Hg), respectively. The molecular structures of 1Hg, 2Hg and 3Hg show considerable differences. In complex 1Hg, a single bridging bidentate ligand connects two three-coordinate T-shape mercury atoms with a near linear C-Hg-C atom array. Complex 2Hg is a one-dimensional coordination polymer in which adjacent four-coordinate mercury atoms with a linear C-Hg-C atom array are linked by bridging bidentate O,O'- ligands, whilst in complex 3Hg a T-shape three-coordinate mercury atom is ligated by (3) in a monodentate fashion. The Hg-O bond lengths of complexes 1Hg, 2Hg and 3Hg differ substantially (range 2.5373(14)-2.966(3) angstrom) owing to structural and bonding differences.