Trans-3- lanthanide-coordination chemistry

Cyclam, or 1,4,8,11-tetraazacyclotetradecane is a popular macrocyclic ligand for d-tran-sition metal coordination chemistry. It also coordinates to lanthanide ions, although much less strongly than the better size-adapted cyclen. As for the latter, however, derivatization of the amine functions by amide, carboxylate, or phosphinate groups considerably improves the coordination ability of the macrocycle. 

Jauregui M, Perry WS, Allain C, Vidler LR, Willis MC, Kenwright AM, Stasiuk G, Lowe MP, Faulkner S (2009) Changing the local coordination environment in mono- and bi-nuclear lanthanide complexes through click chemistry. Dalton Trans 6283-6285... 

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