Ruthenium(II) complexes containing 8-(dimethylphosphino)quinoline (Me2Pqn)

Preparation, crystal structures, and electrochemical and spectroscopic properties of [Ru(bpy or phen)3-n(Me2Pqn)n] (PF6)2 (bpy = 2,2′-bipyridine; phen = 1,10-phenanthroline; n = 1, 2, or 3)

Takayoshi Suzuki, Takashi Kuchiyama, Shinobu Kishi, Sumio Kaizaki, Hideo D. Takagi, Masako Kato

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38 Citations (Scopus)

Abstract

Several new ruthenium(II) complexes containing 8-(dimethylphosphino)quinoline (Me2Pqn) were synthesized, and their structures and electrochemical/spectroscopic properties have been investigated. In addition to the mono(Me2Pqn) complex [Ru(bpy or phen)2(Me2Pqn)](PF6)2 (1 or 1′; bpy = 2,2′-bipyridine; phen = 1,10-phenanthroline), the geometrical isomers trans(P)- and C1-[Ru(bpy)(Me2Pqn)2] (PF6)2 (tP-2 and C1-2) and mer- and fac-[Ru(Me2Pqn)3](PF6)2 (m-3 and f-3) were also selectively synthesized and isolated. It was found that complexes tP-2 and m-3 were converted quantitatively to the corresponding C1-2 and f-3 isomers, respectively, by irradiation of light corresponding to the MLCT transition energy. The strong trans influence of the Me2P- donor group of Me2Pqn was confirmed by the X-ray structural analyses for 1, tP-2, m-3, and f-3. Cyclic voltammetry of a series of complexes, [Ru(bpy)3](PF6)2, 1, C1-2, and f-3, exhibited a reversible one-electron oxidation wave and two or three one-electron reduction waves. The oxidation potentials of the complexes gave a large positive shift with increasing number of coordinated Me2Pqn molecules, indicating a larger π-acceptability of the Me2P- group compared with bpy or qn, Complex f-3 in EtOH/MeOH (4:1) glass at 77 K exhibited an intense long-lived (τ = 920 μs) emission arising from the quinoline-based 3(π-π*) excited state. In contrast, the mixed-ligand complexes 1, 1′, and C1-2 showed a characteristic dual emission, giving a double-exponential emission decay, and the dual emission originates from both the bpy-based 3MLCT and the quinoline-based 3(π-π*) emitting states.

Original languageEnglish
Pages (from-to)785-795
Number of pages11
JournalInorganic Chemistry
Volume42
Issue number3
DOIs
Publication statusPublished - Feb 10 2003
Externally publishedYes

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Ruthenium
quinoline
ruthenium
Crystal structure
Isomers
preparation
crystal structure
Oxidation
isomers
Electrons
Excited states
oxidation
Cyclic voltammetry
Irradiation
acceptability
Ligands
X rays
Glass
Molecules
electrons

ASJC Scopus subject areas

  • Inorganic Chemistry

Cite this

@article{99aca17bb76442128c8e4bed312a3aa0,
title = "Ruthenium(II) complexes containing 8-(dimethylphosphino)quinoline (Me2Pqn): Preparation, crystal structures, and electrochemical and spectroscopic properties of [Ru(bpy or phen)3-n(Me2Pqn)n] (PF6)2 (bpy = 2,2′-bipyridine; phen = 1,10-phenanthroline; n = 1, 2, or 3)",
abstract = "Several new ruthenium(II) complexes containing 8-(dimethylphosphino)quinoline (Me2Pqn) were synthesized, and their structures and electrochemical/spectroscopic properties have been investigated. In addition to the mono(Me2Pqn) complex [Ru(bpy or phen)2(Me2Pqn)](PF6)2 (1 or 1′; bpy = 2,2′-bipyridine; phen = 1,10-phenanthroline), the geometrical isomers trans(P)- and C1-[Ru(bpy)(Me2Pqn)2] (PF6)2 (tP-2 and C1-2) and mer- and fac-[Ru(Me2Pqn)3](PF6)2 (m-3 and f-3) were also selectively synthesized and isolated. It was found that complexes tP-2 and m-3 were converted quantitatively to the corresponding C1-2 and f-3 isomers, respectively, by irradiation of light corresponding to the MLCT transition energy. The strong trans influence of the Me2P- donor group of Me2Pqn was confirmed by the X-ray structural analyses for 1, tP-2, m-3, and f-3. Cyclic voltammetry of a series of complexes, [Ru(bpy)3](PF6)2, 1, C1-2, and f-3, exhibited a reversible one-electron oxidation wave and two or three one-electron reduction waves. The oxidation potentials of the complexes gave a large positive shift with increasing number of coordinated Me2Pqn molecules, indicating a larger π-acceptability of the Me2P- group compared with bpy or qn, Complex f-3 in EtOH/MeOH (4:1) glass at 77 K exhibited an intense long-lived (τ = 920 μs) emission arising from the quinoline-based 3(π-π*) excited state. In contrast, the mixed-ligand complexes 1, 1′, and C1-2 showed a characteristic dual emission, giving a double-exponential emission decay, and the dual emission originates from both the bpy-based 3MLCT and the quinoline-based 3(π-π*) emitting states.",
author = "Takayoshi Suzuki and Takashi Kuchiyama and Shinobu Kishi and Sumio Kaizaki and Takagi, {Hideo D.} and Masako Kato",
year = "2003",
month = "2",
day = "10",
doi = "10.1021/ic020344l",
language = "English",
volume = "42",
pages = "785--795",
journal = "Inorganic Chemistry",
issn = "0020-1669",
publisher = "American Chemical Society",
number = "3",

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TY - JOUR

T1 - Ruthenium(II) complexes containing 8-(dimethylphosphino)quinoline (Me2Pqn)

T2 - Preparation, crystal structures, and electrochemical and spectroscopic properties of [Ru(bpy or phen)3-n(Me2Pqn)n] (PF6)2 (bpy = 2,2′-bipyridine; phen = 1,10-phenanthroline; n = 1, 2, or 3)

AU - Suzuki, Takayoshi

AU - Kuchiyama, Takashi

AU - Kishi, Shinobu

AU - Kaizaki, Sumio

AU - Takagi, Hideo D.

AU - Kato, Masako

PY - 2003/2/10

Y1 - 2003/2/10

N2 - Several new ruthenium(II) complexes containing 8-(dimethylphosphino)quinoline (Me2Pqn) were synthesized, and their structures and electrochemical/spectroscopic properties have been investigated. In addition to the mono(Me2Pqn) complex [Ru(bpy or phen)2(Me2Pqn)](PF6)2 (1 or 1′; bpy = 2,2′-bipyridine; phen = 1,10-phenanthroline), the geometrical isomers trans(P)- and C1-[Ru(bpy)(Me2Pqn)2] (PF6)2 (tP-2 and C1-2) and mer- and fac-[Ru(Me2Pqn)3](PF6)2 (m-3 and f-3) were also selectively synthesized and isolated. It was found that complexes tP-2 and m-3 were converted quantitatively to the corresponding C1-2 and f-3 isomers, respectively, by irradiation of light corresponding to the MLCT transition energy. The strong trans influence of the Me2P- donor group of Me2Pqn was confirmed by the X-ray structural analyses for 1, tP-2, m-3, and f-3. Cyclic voltammetry of a series of complexes, [Ru(bpy)3](PF6)2, 1, C1-2, and f-3, exhibited a reversible one-electron oxidation wave and two or three one-electron reduction waves. The oxidation potentials of the complexes gave a large positive shift with increasing number of coordinated Me2Pqn molecules, indicating a larger π-acceptability of the Me2P- group compared with bpy or qn, Complex f-3 in EtOH/MeOH (4:1) glass at 77 K exhibited an intense long-lived (τ = 920 μs) emission arising from the quinoline-based 3(π-π*) excited state. In contrast, the mixed-ligand complexes 1, 1′, and C1-2 showed a characteristic dual emission, giving a double-exponential emission decay, and the dual emission originates from both the bpy-based 3MLCT and the quinoline-based 3(π-π*) emitting states.

AB - Several new ruthenium(II) complexes containing 8-(dimethylphosphino)quinoline (Me2Pqn) were synthesized, and their structures and electrochemical/spectroscopic properties have been investigated. In addition to the mono(Me2Pqn) complex [Ru(bpy or phen)2(Me2Pqn)](PF6)2 (1 or 1′; bpy = 2,2′-bipyridine; phen = 1,10-phenanthroline), the geometrical isomers trans(P)- and C1-[Ru(bpy)(Me2Pqn)2] (PF6)2 (tP-2 and C1-2) and mer- and fac-[Ru(Me2Pqn)3](PF6)2 (m-3 and f-3) were also selectively synthesized and isolated. It was found that complexes tP-2 and m-3 were converted quantitatively to the corresponding C1-2 and f-3 isomers, respectively, by irradiation of light corresponding to the MLCT transition energy. The strong trans influence of the Me2P- donor group of Me2Pqn was confirmed by the X-ray structural analyses for 1, tP-2, m-3, and f-3. Cyclic voltammetry of a series of complexes, [Ru(bpy)3](PF6)2, 1, C1-2, and f-3, exhibited a reversible one-electron oxidation wave and two or three one-electron reduction waves. The oxidation potentials of the complexes gave a large positive shift with increasing number of coordinated Me2Pqn molecules, indicating a larger π-acceptability of the Me2P- group compared with bpy or qn, Complex f-3 in EtOH/MeOH (4:1) glass at 77 K exhibited an intense long-lived (τ = 920 μs) emission arising from the quinoline-based 3(π-π*) excited state. In contrast, the mixed-ligand complexes 1, 1′, and C1-2 showed a characteristic dual emission, giving a double-exponential emission decay, and the dual emission originates from both the bpy-based 3MLCT and the quinoline-based 3(π-π*) emitting states.

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U2 - 10.1021/ic020344l

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JF - Inorganic Chemistry

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