%0 Journal Article %1 Mondal.2014d %A Mondal, Prasenjit %A Agarwala, Hemlata %A Jana, Rahul Dev %A Plebst, Sebastian %A Grupp, Anita %A Ehret, Fabian %A Mobin, Shaikh M. %A Kaim, Wolfgang %A Lahiri, Goutam Kumar. %D 2014 %J Inorganic Chemistry %K DFT EPR acetylacetonato bisphenyliminoacenaphthene calcn complex complex;ruthenium crystal electrochem prepn ruthenium structure tetrakispyridylpyrazine %N 14 %P 7389--7403 %R 10.1021/ic500730m %T Sensitivity of a Strained C-C Single Bond to Charge Transfer: Redox Activity in Mononuclear and Dinuclear Ruthenium Complexes of Bis(arylimino)acenaphthene (BIAN) Ligands %V 53 %X [Ru(acac)2(BIAN)], BIAN = bis(arylimino)acenaphthene (aryl = Ph (1a), 4-MeC6H4 (2a), 4-OMeC6H4 (3a), 4-ClC6H4 (4a), 4-NO2C6H4 (5a)), were synthesized and structurally, electrochem., spectroscopically, and computationally characterized. The a-diimine sections of the compds. exhibit intrachelate ring bond lengths 1.304 \AA \textless d(CN) \textless 1.334 and 1.425 \AA \textless d(CC) \textless 1.449 \AA, which indicate considerable metal-to-ligand charge transfer in the ground state, approaching a RuIII(BIAN.bul.-) oxidn. state formulation. The particular structural sensitivity of the strained peri-connecting C-C bond in the BIAN ligands toward metal-to-ligand charge transfer is discussed. Oxidn. of [Ru(acac)2(BIAN)] produces EPR and UV-visible-NIR (NIR = near IR) spectroelectrochem. detectable RuIII species, while the redn. yields predominantly BIAN-based spin, in agreement with d. functional theory (DFT) spin-d. calcns. Variation of the substituents from CH3 to NO2 has little effect on the spin distribution but affects the absorption spectra. Dinuclear (μ-tppz)[Ru(Cl)(BIAN)]2(ClO4)2, tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine; aryl (BIAN) = Ph ([1b](ClO4)2), 4-MeC6H4 ([2b](ClO4)2), 4-OMeC6H4 ([3b](ClO4)2), 4-ClC6H4 ([4b](ClO4)2), were also obtained and investigated. The structure detn. of [2b](ClO4)2 and [3b](ClO4)2 reveals trans configuration of the chloride ligands and unreduced BIAN ligands. The DFT and spectroelectrochem. results (UV-visible-NIR, EPR) indicate oxidn. to a weakly coupled RuIIIRuII mixed-valent species but redn. to a tppz-centered radical state. The effect of the p electron-accepting BIAN ancillary ligands is to diminish the metal-metal interaction due to competition with the acceptor bridge tppz. [on SciFinder(R)]

@article{Mondal.2014d, abstract = {[Ru(acac)2(BIAN)], BIAN = bis(arylimino)acenaphthene (aryl = Ph (1a), 4-MeC6H4 (2a), 4-OMeC6H4 (3a), 4-ClC6H4 (4a), 4-NO2C6H4 (5a)), were synthesized and structurally, electrochem., spectroscopically, and computationally characterized. The \textgreek{a}-diimine sections of the compds. exhibit intrachelate ring bond lengths 1.304 {\AA} {\textless} d(CN) {\textless} 1.334 and 1.425 {\AA} {\textless} d(CC) {\textless} 1.449 {\AA}, which indicate considerable metal-to-ligand charge transfer in the ground state, approaching a RuIII(BIAN.bul.-) oxidn. state formulation. The particular structural sensitivity of the strained peri-connecting C-C bond in the BIAN ligands toward metal-to-ligand charge transfer is discussed. Oxidn. of [Ru(acac)2(BIAN)] produces EPR and UV-visible-NIR (NIR = near IR) spectroelectrochem. detectable RuIII species, while the redn. yields predominantly BIAN-based spin, in agreement with d. functional theory (DFT) spin-d. calcns. Variation of the substituents from CH3 to NO2 has little effect on the spin distribution but affects the absorption spectra. Dinuclear {(μ-tppz)[Ru(Cl)(BIAN)]2}(ClO4)2, tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine; aryl (BIAN) = Ph ([1b](ClO4)2), 4-MeC6H4 ([2b](ClO4)2), 4-OMeC6H4 ([3b](ClO4)2), 4-ClC6H4 ([4b](ClO4)2), were also obtained and investigated. The structure detn. of [2b](ClO4)2 and [3b](ClO4)2 reveals trans configuration of the chloride ligands and unreduced BIAN ligands. The DFT and spectroelectrochem. results (UV-visible-NIR, EPR) indicate oxidn. to a weakly coupled RuIIIRuII mixed-valent species but redn. to a tppz-centered radical state. The effect of the \textgreek{p} electron-accepting BIAN ancillary ligands is to diminish the metal-metal interaction due to competition with the acceptor bridge tppz. [on SciFinder(R)]}, added-at = {2022-06-15T11:26:56.000+0200}, author = {Mondal, Prasenjit and Agarwala, Hemlata and Jana, Rahul Dev and Plebst, Sebastian and Grupp, Anita and Ehret, Fabian and Mobin, Shaikh M. and Kaim, Wolfgang and Lahiri, Goutam Kumar.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2407a9f92187861fb201adf6a13b4a935/huebleriac}, doi = {10.1021/ic500730m}, interhash = {cb3fb851b57939848e82c034871e6472}, intrahash = {407a9f92187861fb201adf6a13b4a935}, issn = {0020-1669}, journal = {Inorganic Chemistry}, keywords = {DFT EPR acetylacetonato bisphenyliminoacenaphthene calcn complex complex;ruthenium crystal electrochem prepn ruthenium structure tetrakispyridylpyrazine}, number = 14, pages = {7389--7403}, timestamp = {2022-06-15T09:26:56.000+0200}, title = {Sensitivity of a Strained C-C Single Bond to Charge Transfer: Redox Activity in Mononuclear and Dinuclear Ruthenium Complexes of Bis(arylimino)acenaphthene (BIAN) Ligands}, volume = 53, year = 2014 }