TY - JOUR
T1 - Synthesis and properties of a mixed-valence compound with single-step tunneling and multiple-step hopping behavior
AU - Makhoul, Rim
AU - Kumamoto, Yuki
AU - Miyazaki, Akira
AU - Justaud, Frédéric
AU - Gendron, Frédéric
AU - Halet, Jean François
AU - Hamon, Jean René
AU - Lapinte, Claude
N1 - Publisher Copyright:
Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
PY - 2014/8/1
Y1 - 2014/8/1
N2 - The organic precursor bis(trimethylsilylethynyl)TTFMe2 (3, TTF = tetrathiafulvalene) was prepared as a 1:1 mixture of the cis and trans isomers. Pure samples of 3-cis and 3-trans were obtained by crystallization and identified by XRD analysis. The treatment of pure 3-trans and a 1:1 mixture of 3-cis/trans with (i) potassium carbonate, (ii) the iron complex Cp∗(dppe)FeCl [5, Cp∗ = η5-C5Me5, dppe = 1,2-bis(diphenylphosphanyl)ethane] in the presence of KPF6, and (iii) tBuOK provided Cp∗(dppe)Fe-C≡C-TTFMe2-C≡C-Fe(dppe)Cp∗ as the pure geometric isomer 6-trans (85 %) and as the 60:40 mixture 6-cis/trans (63 %), respectively. The oxidation of 6-trans with [(C5H5)2Fe]PF6 gave [6-trans][PF6]n (n = 1-3). Visible, IR, near-IR (NIR), and electron paramagnetic resonance (EPR) spectroscopy together with DFT data show that [6-trans][PF6] is a class II mixed-valence complex (Hab = 85 cm-1) in which the spin distribution depends on the conformation of the molecule. Intramolecular electron transfer occurs through single-step tunneling and a multistep hoping mechanism. The triplet state is thermally accessible for [6-trans][PF6]2. The complex trans-[Cp∗(dppe)Fe-C≡C-TTFMe2-C≡C-Fe(dppe)Cp∗][PF6] [Cp∗ = η5-C5Me5, dppe = 1,2-bis(diphenylphosphanyl)ethane, TTF = tetrathiafulvalene] is a class II mixed-valence compound in which the spin density varies with the respective orientation of the metal termini. Intramolecular electron transfer occurs through single-step tunneling and multiple-step hopping mechanisms.
AB - The organic precursor bis(trimethylsilylethynyl)TTFMe2 (3, TTF = tetrathiafulvalene) was prepared as a 1:1 mixture of the cis and trans isomers. Pure samples of 3-cis and 3-trans were obtained by crystallization and identified by XRD analysis. The treatment of pure 3-trans and a 1:1 mixture of 3-cis/trans with (i) potassium carbonate, (ii) the iron complex Cp∗(dppe)FeCl [5, Cp∗ = η5-C5Me5, dppe = 1,2-bis(diphenylphosphanyl)ethane] in the presence of KPF6, and (iii) tBuOK provided Cp∗(dppe)Fe-C≡C-TTFMe2-C≡C-Fe(dppe)Cp∗ as the pure geometric isomer 6-trans (85 %) and as the 60:40 mixture 6-cis/trans (63 %), respectively. The oxidation of 6-trans with [(C5H5)2Fe]PF6 gave [6-trans][PF6]n (n = 1-3). Visible, IR, near-IR (NIR), and electron paramagnetic resonance (EPR) spectroscopy together with DFT data show that [6-trans][PF6] is a class II mixed-valence complex (Hab = 85 cm-1) in which the spin distribution depends on the conformation of the molecule. Intramolecular electron transfer occurs through single-step tunneling and a multistep hoping mechanism. The triplet state is thermally accessible for [6-trans][PF6]2. The complex trans-[Cp∗(dppe)Fe-C≡C-TTFMe2-C≡C-Fe(dppe)Cp∗][PF6] [Cp∗ = η5-C5Me5, dppe = 1,2-bis(diphenylphosphanyl)ethane, TTF = tetrathiafulvalene] is a class II mixed-valence compound in which the spin density varies with the respective orientation of the metal termini. Intramolecular electron transfer occurs through single-step tunneling and multiple-step hopping mechanisms.
KW - Conjugated systems
KW - Hybrid materials
KW - Iron
KW - Mixed-valent compounds
KW - Molecular electronics
UR - http://www.scopus.com/inward/record.url?scp=85027932836&partnerID=8YFLogxK
U2 - 10.1002/ejic.201402022
DO - 10.1002/ejic.201402022
M3 - 学術論文
AN - SCOPUS:85027932836
SN - 1434-1948
VL - 2014
SP - 3899
EP - 3911
JO - European Journal of Inorganic Chemistry
JF - European Journal of Inorganic Chemistry
IS - 24
ER -