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Two new chain complexes consisting of a Mn(salen) building block bridged by O–Se–O units, [Mn2(salen)2(L)](ClO4) (1) and {[Mn(salen)]2(L)2}·Y (2) (salen = N,N′-bis(salicylidene)-ethylenediamine, L = 3,4,5-trifluorobenzeneseleninic acid, Y = salicylaldehyde) have been synthesized and characterized structurally and magnetically. In the two complexes above, the 3,4,5-trifluorobenzeneseleninic acid ligand adopts a syn–anti bridging coordination mode and all the MnIII ions show a distorted octahedral geometry. In complex 1, the [Mn2(salen)2]2+ dimers are connected alternatively by the bridging ligands into an infinite zigzag chain, while the [Mn(salen)]+ monomers are connected alternatively in complex 2. The magnetic measurements reveal that both complexes exhibit slow magnetic relaxation behaviours with an effective energy barrier Ueff = 31.2 K for 1 and Ueff = 35.1 K for 2, respectively. These compounds are rare examples of a small number of aromatic selenite based magnetic materials. [ABSTRACT FROM AUTHOR]

A new copper Schiff-base complex [Cu(C15H23N3O2)(NO3)]NO3 was synthesized and characterized by spectroscopic (IR), thermal (TG/DTA) and electrochemical methods. Single crystal X-ray diffraction revealed that the complex is monoclinic, space group P2(1)/c, with a = 23.549(2), b = 6.583(12), c = 12.765(15) Å, β = 102.823(2)°, V = 1929.4(5) Å3, Z = 4, Dcalcd = 1.601 Mg m-3, F(000) = 964, goodness-of-fit = 1.034 and R1 = 0.0407. The Cu(II) is four-coordinate with distorted square planar geometry. The structure consists of isolated [Cu(C15H23N3O2)(NO3)]+ and a nitrate, which are further linked to a 3D network by significant N-H ··· O, N-H ··· N hydrogen bonds and weak O ··· Cu interaction. [ABSTRACT FROM AUTHOR]

Abstract: Complex [Cu4(HL)4]·DMF (1) (H3L=N′-(2-hydroxy-3-methoxybenzylidene)-2-hydroxybenzo-hydrazide), has been prepared by using Schiff base ligand and characterized by X-ray single crystal diffraction, FT-IR, elemental analysis and TG analysis. The complex contains a pseudo-cubic Cu4O4 skeleton which is further arranged into micropores 3D supramolecular framework via multiple Cπ and CO interactions. Fitting the temperature dependent magnetic susceptibility of 1 confirms an antiferromagnetic behavior with J =−37.46K and J′ =−2.45K. [Copyright &y& Elsevier]

The title compound, C17H16Cl2N2, adopts a `vault' conformation. The mol­ecules are linked by a pair of C—H⋯N hydrogen bonds into a centrosymmetric dimer with an R22(18) ring. These dimers are linked by a weak centrosymmetric π–π inter­action into a chain along the [001] direction, and these chains are connected by van der Waals inter­actions, resulting in a three-dimensional network structure. [ABSTRACT FROM AUTHOR]

The title compound, C50H68N6O8, is a new Schiff base compound synthesized by the condensation reaction of paeonol and N, N, N′, N′-tetra­kis(3-amino­prop­yl)ethyl­ene­diamine in absolute methanol. The mol­ecule possesses a crystallographically imposed centre of symmetry and demonstrates normal values of bond lengths and angles. [ABSTRACT FROM AUTHOR]

In the title compound, C19H18N2O4, the methyl group is disordered. The mol­ecule is centrosymmetric and has a trans configuration ( E, E). [ABSTRACT FROM AUTHOR]

Abstract: Reactions of pyruvic acid hydrazone series [pyruvic acid thiophenecarbonyl hydrazone (L1), pyruvic acid 4-hydroxybenzoylhydrazone (L2), pyruvic acid salicyloylhydrazone (L3), pyruvic acid benzoylhydrazone (L4)], or salicylaldehyde hydrazone Schiff base ligand [salicylaldehyde isonicotinoylhydrazone (L5)] with different alkyltin salts result in six new organotin(IV) compounds, {(n-Bu)2Sn[2-SC4H3CON2C(CH3)CO2](HOC3H7-i)}2 (1), [{(n-Bu)2SnCl(O)(n-Bu)2 Sn(O)[C6H4CON2C(CH3)CO2]Sn(n-Bu)2(HOCH3)}2]∞ (2), {(o-ClBz)2Sn[4-HOC6H4CON2C(CH3) CO2] (HOC2H5)}2 (3), {(n-C8H17)2Sn[2-HOC6H4CON2C(CH3)CO2](H2O)}2 (4), {(n-Bu)2Sn[C6H5 CON2C(CH3)CO2][HOSn(n-Bu)3]}2 (5), and {[(n-C4H9)SnCl2]−[4-NHC5H4CON2CH (C6H4O-2)]+ (6), which have been characterized by single crystal X-ray diffraction, elemental analysis, IR, 1H and 119Sn NMR. In compounds 1, 3, 4, weak-bridged dimers are found, in which the two tin atoms are linked by a pair of monodentate bridges. Each pyruvic acid hydrazone ligand serves as an enolic tridentatic ligand. Compound 2 contains dimeric units of {Sn6(L2)2(n-Bu)6(HOCH3)2} that are further connected by two pairs of monodentate bridges into an 1D weak-bridged polymeric chain, in which there also exists a fascinating dichlorodistannoxane ladder structure. Studies show that the bulk and steric hindrance of the alkyl groups and the coordinated solvent molecule bonding to Sn center have little effect on the geometry of the weak-bridge for compounds 1–4. A similar weak-bridged dimeric structure is also found in compound 5; in this case, however, there is no coordinated solvent molecule and the corresponding coordination site is replaced by the trialkyltin hydroxide. Compound 6 exhibits a rare 1D supermolecular chain constructed from the zwitterionic {Sn(L5)(n-Bu)Cl2} units connected by the intermolecular N–H⋯Cl hydrogen bonds. The thermal stability of compound 1 was also studied. [Copyright &y& Elsevier]

Abstract: Eight diorganotin esters of Schiff base ligands formulated as [R2SnLY]2, where L1 is 4-NC5H4CON2C(CH3) CO2 with Y=H2O, R=Ph (1), PhCH2 (2), m-ClC6H4CH2 (3), and L2 is 2-HOC6H4CON2C(CH3) CO2 with Y=CH3OH, R=PhCH2 (4), o-ClC6H4CH2 (5), m-ClC6H4CH2 (6), o-FC6H4CH2 (7), p-FC6H4CH2 (8) have been prepared and characterized by elemental analysis, IR, 1H and 119Sn NMR spectra. The crystal structures of compounds 1, 2 and 4 have been determined by X-ray single crystal diffraction. Their structures show that the tin atoms of three compounds are all rendered seven-coordinated in distorted pentagonal bipyramid geometries with a planar SnO4N unit and two apical aryl carbon atoms. A comparison of the IR spectra of the ligands with those of the corresponding compounds, reveals that the disappearance of the bands assigned to carbonyl unambiguously conforms that the ligands coordinate with tin in the enol form. [Copyright &y& Elsevier]

The title complex, [ZnCl2(C16H17NO2)2], displays a distorted tetra­hedral coordination geometry around the ZnII ion. The Schiff base inner salt, (benzyl­imino)ethyl-5-methoxy­phenol, coordinates in a monodentate manner to the ZnII ion via the deprotonated hydr­oxy groups. The protonated imino groups form intra­molecular hydrogen bonds with the deprotonated hydroxyl groups of the same Schiff base ligand. [ABSTRACT FROM AUTHOR]