Bismuth Atoms in Hydrocarbon Ligands: Bismepines as Rigid, Ditopic Arene Donors in Coordination Chemistry

Dibenzobismepines
may be described as bismuth heterocycles containing
two arene functional groups (see the graphic). The coordination chemistry
of mono- and dinuclear bismepines has been investigated in solution
and in the solid state, demonstrating that they can act as a new class
of rigid, ditopic arene ligands. In contrast to the lighter N, P,
and As homologues, the bismuth atom does not directly interact with
the metal atom but influences the ligand properties through its energetically
low lying 6s orbital, its low electronegativity, and its unusual bond
lengths and angles. Analytical techniques applied in this work include
(DOSY) NMR spectroscopy, single-crystal X-ray analysis, mass spectrometry,
and DFT calculations.