Yeo, Benjamin Roy, Hallett, Andrew Jon, Kariuki, Benson ![]() ![]() |
Abstract
Reaction of 2,3-diaminopyridine with one equivalent of a functionalised vicinal diketone, in ethanol, yields a series of ligands based upon the pyrido[2,3-b]pyrazine core. The ligands were characterised by 1H, 13C–{1H} NMR, MS and UV–Vis spectroscopy. Reaction of the ligands with one equivalent of {ReBr(CO)5} gave a series of Re-Ln complexes based upon the general formula fac-{ReBr(CO)3(L)} (where L = pyrido[2,3-b]pyrazine-derived ligands, L1–L6). Solution IR studies confirmed the retention of the facially capped, tri-carbonyl coordination geometry at rhenium, and 1H NMR studies confirmed coordination of the ligand to Re(I). EI HR MS data were obtained for each complex confirming the proposed formulation and stoichiometry. Single crystal X-ray structures were obtained for three of the complexes (Re-L1, Re-L2, Re-L6), with each demonstrating that the ligands coordinate to Re(I) in a bidentate manner, via a four-membered chelate ring, which was unsymmetrical in the former two cases. The electronic absorption spectra of the complexes showed absorption into the visible region ca. 375–500 nm, (the complexes are orange-red in appearance). Following irradiation at 350–450 nm, the complexes display a solid-state broad emission peaking between 600–700 nm. The complexes were not sufficiently luminescent in solution to allow further investigation into the origin of this emission band, although with reference to related 1,8-naphthyridine complexes of Re(I) it is likely to incorporate significant 3MLCT character
Item Type: | Article |
---|---|
Date Type: | Publication |
Status: | Published |
Schools: | Chemistry |
Subjects: | Q Science > QD Chemistry |
Uncontrolled Keywords: | Heterocycles ; Coordination chemistry ; Rhenium complex ; Spectroscopy ; X-ray structures |
Publisher: | Elsevier |
ISSN: | 0277-5387 |
Last Modified: | 18 Oct 2022 12:24 |
URI: | https://orca.cardiff.ac.uk/id/eprint/9698 |
Citation Data
Cited 15 times in Scopus. View in Scopus. Powered By Scopus® Data
Actions (repository staff only)
![]() |
Edit Item |