Modifying the Donor Properties of Tris(pyridyl)aluminates in Lanthanide (II) Sandwich Compounds

26 Jun 2018

The coordination ability of tris(pyridyl)aluminates can be modified by the steric and electronic character of substituents at the 6-positions of their pyridyl rings. Whereas [EtAl(6-Me-2-py)3]- (1) coordinates strongly to lanthanide (II) ions [Eu(II) and Yb(II)], [EtAl(6-Br-2-py)3]- (2) forms much weaker complexes, and [EtAl(6-CF3-2-py)3]- does not coordinate at all. The modification of the donor ability of these ligands is investigated by solid-state studies of the Ln(II) sandwich compounds and by competitive coordination studies in solution.