Versatile Para‐Substituted Pyridine Lanthanide Coordination Complexes Allow Late Stage Tailoring of Complex Function

Starck, Matthieu; Fradgley, Jack D.; De Rosa, Davide F.; Batsanov, Andrei S.; Papa, Maria; Taylor, Michael J.; Lovett, Janet E.; Lutter, Jacob C.; Allen, Matthew J.; Parker, David

Abstract

A series of cationic and neutral p−Br and p−NO2 pyridine substituted Eu(III) and Gd(III) coordination complexes serve as versatile synthetic intermediates. Nucleophilic aromatic substitution occurs readily at the para position under mild conditions, allowing C−N and C−C bond forming reactions to take place, permitting the introduction of azide, amino and alkynyl substituents. For Eu(III) complexes, this approach allows late stage tuning of absorption and emission spectral properties, exemplified by the lowering of the energy of an LMCT transition accompanied by a reduction in the Eu−Npy bond length. Additionally, these complexes provide direct access to the corresponding Eu(II) analogues. With the Gd(III) series, the nature of the p-substituent does not significantly change the EPR properties (linewidth, relaxation times), as required for their development as EPR spin probes that can be readily conjugated to biomolecules under mild conditions.

Citation

Starck, M., Fradgley, J. D., De Rosa, D. F., Batsanov, A. S., Papa, M., Taylor, M. J., Lovett, J. E., Lutter, J. C., Allen, M. J., & Parker, D. (2021). Versatile Para‐Substituted Pyridine Lanthanide Coordination Complexes Allow Late Stage Tailoring of Complex Function. Chemistry - A European Journal, 27(71), 17921-17927. https://doi.org/10.1002/chem.202103243

• Journal Article Type: Article
• Acceptance Date: Oct 27, 2021
• Online Publication Date: Dec 20, 2021
• Publication Date: Dec 20, 2021
• Deposit Date: Jan 26, 2022
• Publicly Available Date: Jan 27, 2022
• Journal: Chemistry – A European Journal
• Print ISSN: 0947-6539
• Electronic ISSN: 1521-3765
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 27
• Issue: 71
• Pages: 17921-17927
• DOI: https://doi.org/10.1002/chem.202103243
• Public URL: https://durham-repository.worktribe.com/output/1215939