Electronically Divergent Triscyclometalated Iridium(III) 2-(1-naphthyl)pyridine Complexes and Their Application in Three-Component Methoxytrifluoromethylation of Styrene
(2019) In Synlett 30(7). p.792-798- Abstract
A systematic study of the photophysical and electrochemical properties of triscyclometalated homoleptic iridium(III) complexes based on 2-(1-naphthyl)pyridine (npy) ligands is presented. A systematic investigation of ligand substitution patterns showed an influence on the lifetime of the excited state, with slight changes in the absorption and emission spectral features. Specifically, the emission lifetime of a complex of an npy ligand substituted with a strongly electron-withdrawing trifluoromethyl group was longer than that of the corresponding complex with the electronically nonperturbed ligand (3.7 μs versus 1.5 μ s). Electronically complementary ligands and complexes... (More)
(Less)
A systematic study of the photophysical and electrochemical properties of triscyclometalated homoleptic iridium(III) complexes based on 2-(1-naphthyl)pyridine (npy) ligands is presented. A systematic investigation of ligand substitution patterns showed an influence on the lifetime of the excited state, with slight changes in the absorption and emission spectral features. Specifically, the emission lifetime of a complex of an npy ligand substituted with a strongly electron-withdrawing trifluoromethyl group was longer than that of the corresponding complex with the electronically nonperturbed ligand (3.7 μs versus 1.5 μ s). Electronically complementary ligands and complexes with orthogonal configurations showed slightly shorter excited state lifetimes compared with unsubstituted npy (1.4-3.0 μs). All complexes displayed reversible or quasireversible redox-couple processes, with the complex of the trifluoromethylated ligand showing the highest ground-state oxidation potential E
1/2
ox
[Ir(III)/Ir(IV) = 0.95 V vs. SCE in CH
2
Cl
2
]. This study showed that these complexes can be used as efficient photoredox catalysts, as demonstrated by their application in a regioselective methoxytrifluoromethylation in which the npy complexes showed equal or better performance compared with the archetypical photo redox catalyst tris[2-phenylpyridinato]iridium(III).
- author
- Njogu, Rachael E.N. ; Fodran, Peter ; Tian, Yuxi LU ; Njenga, Lydia W. ; Kariuki, David K. ; Yusuf, Amir O. ; Scheblykin, Ivan LU ; Wendt, Ola F. LU and Wallentin, Carl Johan LU
- organization
- publishing date
- 2019-01-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- iridium catalysis, ligands, naphthylpyridines, oxytrifluoromethylation, photoredox catalysis, styrene
- in
- Synlett
- volume
- 30
- issue
- 7
- pages
- 7 pages
- publisher
- Georg Thieme Verlag
- external identifiers
-
- scopus:85064269316
- ISSN
- 0936-5214
- DOI
- 10.1055/s-0037-1611716
- language
- English
- LU publication?
- yes
- id
- 86f35fbe-1e88-4525-8a9a-edbdaecc7fb0
- date added to LUP
- 2019-05-03 14:59:26
- date last changed
- 2022-03-10 02:44:30
@article{86f35fbe-1e88-4525-8a9a-edbdaecc7fb0, abstract = {{<p><br> A systematic study of the photophysical and electrochemical properties of triscyclometalated homoleptic iridium(III) complexes based on 2-(1-naphthyl)pyridine (npy) ligands is presented. A systematic investigation of ligand substitution patterns showed an influence on the lifetime of the excited state, with slight changes in the absorption and emission spectral features. Specifically, the emission lifetime of a complex of an npy ligand substituted with a strongly electron-withdrawing trifluoromethyl group was longer than that of the corresponding complex with the electronically nonperturbed ligand (3.7 μs versus 1.5 μ s). Electronically complementary ligands and complexes with orthogonal configurations showed slightly shorter excited state lifetimes compared with unsubstituted npy (1.4-3.0 μs). All complexes displayed reversible or quasireversible redox-couple processes, with the complex of the trifluoromethylated ligand showing the highest ground-state oxidation potential E <br> <sub>1/2</sub><br> <br> <sup>ox</sup><br> [Ir(III)/Ir(IV) = 0.95 V vs. SCE in CH <br> <sub>2</sub><br> Cl <br> <sub>2</sub><br> ]. This study showed that these complexes can be used as efficient photoredox catalysts, as demonstrated by their application in a regioselective methoxytrifluoromethylation in which the npy complexes showed equal or better performance compared with the archetypical photo redox catalyst tris[2-phenylpyridinato]iridium(III). <br> </p>}}, author = {{Njogu, Rachael E.N. and Fodran, Peter and Tian, Yuxi and Njenga, Lydia W. and Kariuki, David K. and Yusuf, Amir O. and Scheblykin, Ivan and Wendt, Ola F. and Wallentin, Carl Johan}}, issn = {{0936-5214}}, keywords = {{iridium catalysis; ligands; naphthylpyridines; oxytrifluoromethylation; photoredox catalysis; styrene}}, language = {{eng}}, month = {{01}}, number = {{7}}, pages = {{792--798}}, publisher = {{Georg Thieme Verlag}}, series = {{Synlett}}, title = {{Electronically Divergent Triscyclometalated Iridium(III) 2-(1-naphthyl)pyridine Complexes and Their Application in Three-Component Methoxytrifluoromethylation of Styrene}}, url = {{http://dx.doi.org/10.1055/s-0037-1611716}}, doi = {{10.1055/s-0037-1611716}}, volume = {{30}}, year = {{2019}}, }