Help Privacy Policy Disclaimer
  Advanced SearchBrowse




Journal Article

First Eu(II)/Ln(III) Mixed Complex with High Oxidative Stability

There are no MPG-Authors in the publication available
External Resource
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available

Wei, Y., & Wang, G. (2015). First Eu(II)/Ln(III) Mixed Complex with High Oxidative Stability. Crystal Growth & Design, 25(11), 5288-5292. doi:10.1021/acs.cgd.5b00804.

Cite as: https://hdl.handle.net/21.11116/0000-0006-9956-D
Due to the instability of divalent europium ions, the heterometallic Eu(II)/Ln(III) complex has not yet been reported. By utilizing coordination chemistry principles, a macrocyclic ligand, N,N′,N″,N‴-tetra(2-hydroxy-3-methoxy-5-methylbenzyl)-1,4,7,10-tetraazacyclododecae (H4L), has been rationally designed to encapsulate Eu2+ and to enable direct formation of the first mixed Eu(II)/Ln(III) complexes, namely, EuII2LnIII4(OH)4(NIC)4L2 (Ln = Sm, Eu, Tb; HNIC = nicotinic acid). Two divalent europium ions are trapped within the macrocyclic cavities of designed ligands L and are further isolated from the environment by outside phenyl rings and the tetrahedral 4Ln(III) cluster, resulting in the enhanced stability of Eu2+. Cyclic voltammetry experiments showed that the oxidation potential of Eu2+ in the heterovalent 2Eu(II)/4Ln(III) cluster is larger than that for the ferrocene/ferrocenium redox couple, which has never been reported previously for Eu2+-containing complexes. Further development of Eu(II) complexes has been limited because Eu2+ could be easily oxidized to Eu3+. The dramatic oxidative stability of as-synthesized complexes not only verifies the synthetic feasibility but also highlights the prospective applications of mixed Eu(II)/Ln(III) coordination complexes.