Synthesis and luminescent properties of heteroleptic lanthanide complexes with oxybenzo[h]quinoline

The heteroligand complexes CpLn(BQ)(2)(DME) (BQ = 10-oxybenzo[h]quinoline, Cp = cyclopen-tadienyl, Ln = La (1), Nd (2), Sm (3), Gd (4)) were synthesised by the reaction of Cp(3)Ln with (BQ)H. The complexes of La, Nd and Sm were structurally characterised. In the case of ytterbium the reaction affords Cp2Yb(BQ)(DME) (5) and homoligand binuclear complex Yb-2(BQ)(6) (6) iregardless of the molar ratio of initial reagents. Upon UV excitation all the complexes gave rise to fluorescence of ligands in the visible region. The photoluminescent spectrum of compound I also contains a phosphorescent band with a lifetime longer than 10 ms. The complexes of Nd, Sm and Yb along with ligand emission display metal-centered luminescent f-f transitions.

Automated summary

A series of heteroligand complexes were synthesized and structurally characterized. Upon UV excitation, these complexes exhibited fluorescence in the visible region, and some of them also showed a long-lived phosphorescent band. The complexes of Nd, Sm, and Yb displayed metal-centered luminescent f-f transitions.