Organomercury compounds. 33 [1] the X-ray crystal structures of Hg(C₆F₄X-p)₂ (X = NH₂, OMe, or Me) - Two examples of supramolecular Lewis acid/base complexes

The X-ray crystal structures of Hg(C₆F₄X-p)₂ (X = NH₂, OMe, or Me) show the compounds to have almost linear C-Hg-C stereochemistry (X = NH₂, 176.3(4)°; X = OMe, 179.5(2)°; X = Me, 176.3(2)°), and the two tetrafluoroaryl rings rotated ca. 52-62° with respect to each other. Substantial conjugation of NH2 and OMe groups with the aromatic rings is evident from N-C and O-C(Ar) disv tances. For X = NH₂ or OMe, two weak N(O)-Hg coordination interactions per mercury lead to a two dimensional supramolecular chain structure containing pairs of π-stacked aromatic rings at near van der Waals contact distances rotated at 62.2° (X = NH2) or 52.9° (X = OMe) to each other. In Hg(C₆F₄Me-p)₂, which does not have potential donor atoms, no supramolecular structure is obtained, the molecules being laterally displaced from one another.