A simple synthesis and a structural survey of homoleptic rare earth(III) 2,6-diphenylphenolates

Reactions of 2,6-diphenylphenol (HOdpp) and rare earth metals, in the prese nce of mercury, at elevated temperatures in sealed tubes followed by extrac tion with toluene yielded homoleptic tris(aryloxo)lanthanoid(III) complexes , [Ln(Odpp)(3)] (Ln = Y (1), La (2), Ce (3), Pr (4), Nd (5), Gd (6), Ho (7) , Er (8), Lu (9)). Single crystal X-ray diffraction studies of 1-4 and 9 es tablished monomeric structures with the coordination sphere comprising a tr iangular array of Odpp oxygen atoms with capping phenyl groups above and be low. In the isomorphous (triclinic <P(1)over bar>) 1, 3, 4 and 9, there are additional intramolecular pi-interactions of the phenyl substituents with the metals (eta(6)-Ph-Ln and eta(1)-Ph-Ln). The cell parameters for 2, thou gh similar, suggest a different form, and the structure has additional intr amolecular eta(6)-Ph-La and eta(3)-Ph-La interactions with the capping phen yl groups near parallel.