Chiral probe development for circularly polarised luminescence: comparative study of structural factors determining the degree of induced CPL with four heptacoordinate europium(III) complexes

Neil, E.R.; Fox, M.A.; Pal, R.; Pålsson, L.O.; O'Sullivan, B.A.; Parker, D.

Abstract

A series of bright, europium(III) complexes has been prepared based on an achiral heptadentate triazacyclononane ligand bearing two strongly absorbing, coordinated aralkynyl pyridyl moieties. The binding of chiral carboxylates, including α-hydroxy acids such as lactate and mandelate, has been monitored by emission spectroscopy and is signalled by the switching on of strong circularly polarised emission. In each case, an R-chiral carboxylate gave rise to emission typical of a Δ complex, most clearly shown in the form of the ΔJ = 4 transition manifold around 700 nm. Variations in the sign and magnitude of the CPL allow the enantiomeric purity and absolute configuration of the acid to be assessed in a sample. Analysis of the relative energies of the parent aqua complexes and their stereoisomeric adducts has been aided by lifetime measurements and density functional theory calculations.

Citation

Neil, E., Fox, M., Pal, R., Pålsson, L., O'Sullivan, B., & Parker, D. (2015). Chiral probe development for circularly polarised luminescence: comparative study of structural factors determining the degree of induced CPL with four heptacoordinate europium(III) complexes. Dalton Transactions, 44(33), 14937-14951. https://doi.org/10.1039/c5dt02358k

• Journal Article Type: Article
• Acceptance Date: Jul 24, 2015
• Publication Date: Sep 7, 2015
• Deposit Date: Sep 22, 2015
• Publicly Available Date: Jul 24, 2016
• Journal: Dalton Transactions
• Print ISSN: 1477-9226
• Electronic ISSN: 1477-9234
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 44
• Issue: 33
• Pages: 14937-14951
• DOI: https://doi.org/10.1039/c5dt02358k
• Public URL: https://durham-repository.worktribe.com/output/1422379