Synthesis and characterisation of dimeric eight-coordinate lanthanide(III) complexes of a macrocyclic tribenzylphosphinate ligand.

Senanayake, K.; Thompson, A.L.; Howard, J.A.K.; Botta, M.; Parker, D.

Abstract

The macrocyclic ligand 1,4,7,10-tetraazacyclododecane-1,4,7-triyl(methylenebenzyl-phosphinic acid) H3L3, has been prepared and its complexes with Eu, Gd and Tb(III) studied by NMR, relaxometry, luminescence and single crystal X-ray crystallography. In solution and in the crystal, the complexes have eight-coordinate metal centres with bridging phosphinate groups linking the two twisted square antiprismatic coordination polyhedra. A single stereoisomer crystallises from solution with an RRR and SSS configuration at the P centres in each sub-unit. The relaxivity of [GdL3]2 is low (1.9 mM−1 s−1, 298 K, 20 MHz), consistent with the absence of any proximate water molecules. The terbium dimer possesses a relatively long excited state lifetime (2.47 ms, 298 K).

Citation

Senanayake, K., Thompson, A., Howard, J., Botta, M., & Parker, D. (2006). Synthesis and characterisation of dimeric eight-coordinate lanthanide(III) complexes of a macrocyclic tribenzylphosphinate ligand. Dalton Transactions, 5423-5428. https://doi.org/10.1039/b612189f

• Journal Article Type: Article
• Online Publication Date: Sep 29, 2006
• Publication Date: 2006
• Journal: Dalton Transactions
• Print ISSN: 1477-9226
• Electronic ISSN: 1477-9234
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Issue: 45
• Pages: 5423-5428
• DOI: https://doi.org/10.1039/b612189f
• Public URL: https://durham-repository.worktribe.com/output/1542161