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Reactions of tptz complexes of Cu(II), Co(II), and Fe(III) with [MV(CN)8]3− (M=Mo, W) anions produced three new heterobimetallic chain compounds (2–4). The mer-capped building block [CuII(tptz)(CF3SO3)2(CH3OH)]·2H2O (1) (tptz=2,4,6-tris(2-pyridyl)-1,3,5-triazine) was also isolated. The structures of 2, 3, and 4 consist of linked squares composed of alternating [MV(CN)8]3− and [M(tptz)]2+/3+ units bridged by cyanide ligands. Both {[CuII(tptz)MoV(CN)8]−·H3O+·CH3OH}∞ (2) and {[FeIII(tptz)WV(CN)8]·2CH3OH}∞ (4) exhibit an infinite ladder-type motif of edge-sharing squares, whereas {[CoII 2(tptz)2(H2O)2W2 V(CN)16CoII(H2O)4]·2H2O}∞ (3) is composed of molecular squares bridged by [Co(H2O)4]2+ cations. The magnetic behavior of 2 is dominated by ferromagnetic coupling between Cu(II) and Mo(V) spin centers. The isostructural compound 4 exhibits weak antiferromagnetic coupling between Fe(III) and W(V) spin centers. In the case of 3, magnetic studies indicate the presence of ferromagnetic interactions between Co(II) and W(V) centers and the ac data reveal a weak out-of-phase signal at low temperature which suggests single-chain magnet behavior. [ABSTRACT FROM AUTHOR]

Abstract: Reactions of the organic donors tetrathiafulvalene (TTF), o-dimethyltetrathiafulvalene (o-Me2TTF), tetramethyltetrathiafulvalene (TMTTF), and tetrathiafulvalene tetrathiolate [TTF(SCH2CH2CN)4] with oxidizing agents of suitable potential resulted in the formation of stable salts in which the donors are present in their monocationic radical forms. The salts presented herein represent a series of reagents containing oxidized chalcofulvalene donors that can be used as starting materials for metathesis reactions with other cations. All of the salts were characterized by X-ray crystallography and UV–vis–NIR spectroscopy. [Copyright &y& Elsevier]

Abstract: Single crystals of two new coordination polymers {Fe(C5N3O)2(CH3CN)2}∞ (1) and {Co(C5N3O)2(C4H4O)2}∞ (2) have been prepared and their structures and magnetic properties determined. Reactions of TCNE with Fe4Cl8(THF)6 in acetonitrile/diethyl ether and TCNE with Co4Cl8(THF)6 in tetrahydrofuran both lead to the transformation of TCNE to 1,2,2-tricyanoethanolate and the formation of two new compounds consisting of infinite, two-dimensional sheets of [Fe(C4N3O)2(CH3CN)2] and [Co(C5N3O)2(C4H4O)2] units with bridging tricyanoethenolate groups. The 1,2,2-tricyanoethanolate ions coordinate to the FeII and CoII centers through two of its three CN groups and not via the O atom. The metal atoms are in slightly distorted octahedral environments with axially bonded acetonitrile and tetrahydrofuran molecules. These sheets are linked by hydrogen bonds involving the ethanolate O atoms and hydrogen atoms of the coordinated solvent molecules. [Copyright &y& Elsevier]

Abstract: Four new salts of the radical cations of TMTSF (tetramethyltetraselenafulvalene), TMTTF (tetramethyltetrathiafulvalene), BEDT-TTF (bisethylenedithiotetrathia-fulvalene) (ET) and o-Me2TTF (o-4,4′-dimethyltetrathiafulvalene) with the metal–metal bonded dianion [Re2Cl8]2− were synthesized, and their structures and physical properties investigated. The structures of these semiconducting salts feature one-dimensional stacking of the donor molecules interleaved with [Re2Cl8]2− anions and interstitial solvent molecules. [Copyright &y& Elsevier]