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Abstract: Two complexes of formulas [Ni(IM-MeImz)2(SCN)2]·CH3CH2OH (1) and [Mn(IM-MeImz)2(SCN)2]·3H2O (2), where IM-MeImz=2-(5-Methylimidazol-4-yl)-4,4,5,5-tetramethyl-2-imidazoline-1-oxyl, have been synthesized and characterized by single-crystal X-ray diffraction. The X-ray analysis demonstrates that IM-MeImz ligand is coordinated to metal ion with the κ2 N(MeImz), O(IM) mode to avoid steric hindrance with the methyl group in complex. In the solid state, the complexes 1 and 2 are linked by intermolecular hydrogen bonds, leading to two-dimensional structure. The variable-temperature magnetic susceptibility of both compounds suggests that the metal ions and radicals are ferromagnetically coupled with J =2.78 and 1.11cm−1 for complexes 1 and 2, respectively. [Copyright &y& Elsevier]

Abstract: A new nitronyl nitroxide NIT2-bithph (1) and its manganese(II) compound [Mn(hfac)2(IMHBithph)]2·(NIT2-bithph)(C6H14) (2) (hfac=hexafluoroacetylacetonate; NIT2-bithph=4,4,5,5-tetramethyl-2-(bithiophenal-2-yl)imidazoline-1-oxyl-3-oxide; IMHBithph=1-hydroxy-2-bithiophenal-4,4,5,5-tetramethyl-4,5-dihydro- 1H-imidazole) have been synthesized and structurally characterized by X-ray diffraction methods. The units of compound 1 were connected as one-dimensional chain by the intermolecular hydrogen bonds which afford an intermolecular antiferromagnetic interaction between nitronyl nitroxide radicals within the chain (J =−1.89cm−1). Compound 2 resulting from the reaction of Mn(hfac)2·2H2O and NIT2-bithph is dinuclear and includes the reduced amidino-oxide form of NIT2-bithph, it is made up of three parts: a [Mn(hfac)2(IMHBithph)]2 dimer unit, an uncoordinated NIT2-bithph radical and a noncoordinated solvent molecule of hexane, the molecule of radical is hydrogen bonded to its reduced form. Two reduced IMHBithph ligands bridge the two manganese(II) ions through their amidino-oxide oxygen atoms resulting in a small intramolecular antiferromagnetic interaction between the manganese ions (J =−1.55cm−1). [Copyright &y& Elsevier]

A novel complex [Zn(NIT2-thz)2(H2O)2]·(ClO4)2 has been synthesized and structurally characterized by X-ray diffraction methods. It crystallizes in the triclinic crystal system and space group PI¯. The structure consists of [Zn(NIT2-thz)2(H2O)2]2+ moiety and two perchlorate anions. The Zinc(II) ion is in a distorted octahedral environment: one nitrogen atom and one oxygen atom from the NIT2-thz, one nitrogen atom and one oxygen atom from another NIT2-thz in the basal plane; two oxygen atoms from the two water molecules in the axial position. The units of [Zn(NIT2-thz)2(H2O)2]2+ were connected as one-dimension chain by the intermolecular hydrogen bonds. The complex exhibits intramolecular antiferromagnetic interactions between the NIT2-thz and the NIT2-thz. [Copyright &y& Elsevier]

Two hydrogen-bonded supramolecular compounds having the general formula [M(H2O)6][H2L] (M=MnII or CoII and H4L=1,2,4,5-benzenetetracarboxylic acid), have been newly prepared by the reaction of [M(H2O)6](ClO4)2 and [C6H2(COOH)4] (H4L), and structurally characterized by X-ray diffraction. The metal center in each compound is six-coordinated, forming an ideal octahedral geometry. Both neutral formula units make unique three-dimensional supramolecular architectures through hydrogen bonds and stabilized by electrostatic force. [Copyright &y& Elsevier]