@article { ISI:000231556400005, title = {2,5-dioxido-1,4-benzoquinonediimine (H2L2-), a hydrogen-bonding noninnocent bridging ligand related to aminated topaquinone: different oxidation state distributions in complexes [{(bpy)(2)Ru}(2)(mu-H2L)](n) (n=0,+,2+,3+,4+) and [{(acac)(2)Ru}(2)(mu-H2L)]}, journal = {Chemistry - a European Journal}, volume = {11}, number = {17}, year = {2005}, month = {AUG}, pages = {4901-4911}, publisher = {WILEY-V C H VERLAG GMBH}, type = {Article}, address = {PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY}, abstract = {

{The symmetrically dinuclear title compounds were isolated as diamagnetic [(bpy)(2)Ru(mu-H2L)Ru(bpy)(2)]- (ClO4)(2) (1-(ClO4)(2)) and as paramagnetic [(acac)(2)Ru(mu-H2L)Ru(acac)(2)] (2) complexes (bpy = 2,2{\textquoteright}-bipyridine; acac(-) -

}, keywords = {bridging ligands, Density functional calculations, EPR spectroscopy, N, O ligands, ruthenium}, issn = {0947-6539}, doi = {10.1002/chem.2005.00202}, author = {Kar, S. and Sarkar, B. and Ghumaan, Sandeep and Janardanan, D. and van Slageren, J. and Fiedler, Jan and Puranik, Vedavati G. and Sunoj, R. B. and Kaim, Wolfgang and Lahiri, Goutam Kumar} } @article { ISI:000226847200018, title = {Tetrazine derived mononuclear Ru-II(acac)(2)(L)(1), [Ru-II(bpy)(2)(L)](ClO4)(2)(2) and [Ru-II(bpy)(L)(2)](ClO4)(2)(3) (L=3-amino-6-(3,5-dimethylpyrazol-1-yl)-1,2,4,5-tetrazine, acac = acetylacetonate, bpy=2,2 {\textquoteright}-bipyridine): syntheses, structures, spectra}, journal = {Polyhedron}, volume = {24}, number = {2}, year = {2005}, month = {JAN}, pages = {333-342}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Mononuclear ruthenium complexes of tetrazine derived L, Ru-II(acac)(2)(L) (1), [Ru-II(bpy)(2)(L)](ClO4)(2) (2) and [Ru-II(bpy)(L)(2)](ClO4)2 (3) (L = 3-amino-6-(3,5-dimethylpyrazol-1-yl)-1,2,4,5-tetrazine, acac = acetylacetonate and bpy = 2,2{\textquoteright}-bipyridine) were prepared. The free L exists as a dimeric entity in the solid state via hydrogen bonding interactions involving L and water molecules present in the crystal lattice. 1 exhibits unusually strong bonds from Ru-II to coordinating pyrazolyl-N (2.040(2) Angstrom) and especially to tetrazine-N (1.913(2) Angstrom). The Ru-III/Ru-II couples of 1-3 appeared at 0.28, 1.34 and 1.50 V versus SCE, respectively. The tetrazine and bpy-based reductions were observed at -1.33 (1); -0.55 and -1.55/-1.75/-1.98 (2); -0.47/-0.78 and -1.80/-2.02 V (3), respectively. 1, 2 and 3 displayed two MLCT bands each, corresponding to dpi(Ru-II) --\> pi* (L, tetrazine) and dpi(Ru-II) --\> pi* (acac or bpy or L) transitions. 1(+) and 2(+) showed rhombic EPR spectra at 110 and 4 K, respectively and 1(-), 2(-) and 3(-) exhibited multiple line EPR spectra at 300 K. 1-3 exhibited moderately strong emission spectra in EtOH-MeOH glass at 77 K. (C) 2004 Elsevier Ltd. All rights reserved.

}, keywords = {Electrochemistry, redox, ruthenium-tetrazine, spectra, structure, synthesis}, issn = {0277-5387}, doi = {10.1016/j.poly.2004.11.019}, author = {Nayak, A. and Patra, S. and Sarkar, B. and Ghumaan, Sandeep and Puranik, Vedavati G. and Kaim, Wolfgang and Lahiri, Goutam Kumar} } @article {31}, title = {Metal-induced reductive ring opening of 1,2,4,5-tetrazines: Three resulting coordination alternatives, including the new non-innocent 1,2-diiminohydrazido(2-) bridging ligand system}, journal = {Inorganic Chemistry}, volume = {45}, number = {3}, year = {2006}, month = {FEB }, pages = {1316-1325}, publisher = {WILEY-V C H VERLAG GMBH}, type = {Article}, address = {BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY}, abstract = {

{Reaction of 3,6-diaryl-1,2,4,5-tetrazines (aryl = R = phenyl, 2-furyl or 2-thienyl) with 2 equiv of Ru(acac)(2)(CH3-CN)(2) results in reductive tetrazine ring opening to yield diruthenium complexes [

}, keywords = {crystal engineering, hydrogen bonds, molecular, recocynition, Self-assembly, supramolecular chemistry}, issn = {0947-6539}, doi = {10.1021/ic051532p}, author = {Maji, Somnath and Sarkar, B. and Patra, S. and Fiedler, Jan and Mobin, Shaikh M. and Puranik, Vedavati G. and Kaim, Wolfgang and Lahiri, Goutam Kumar} }