New CuI complexes of the Schiff‐base‐containing triazole ligands N‐[(E)‐(4‐chlorophenyl)methylidene]‐4H‐1,2,4‐triazol‐4‐amine (ClPhtrz) and N‐[(E)‐phenylmethylidene]‐4H‐1,2,4‐triazol‐4‐amine (Phtrz) have been synthesised and characterised. Depending on the reaction conditions ClPhtrz forms two different dimeric complexes 1 and 2. X‐ray crystallography revealed that each copper centre exhibits a planar trigonal coordination in 1, while the tetrahedral coordination sphere of the copper centre in 2 is completed by a solvent molecule. In dimeric complex 3 the tetrahedral coordination of the CuI ions is formed by two monodentate and two bidentate (bridging) Phtrz ligands. Complexes 1−3 are unstable and easily lose coordinating and/or solvating acetonitrile molecules giving 4 (from 1 and 2) and 5 (from 3). On the basis of ESI MS and 1H NMR and UV/Vis spectroscopy, it was shown that dimeric complexes 1−5 do not survive upon dissolution and dissociate rapidly forming mainly a 1:2 monomeric complex, along with a minor 1:1 complex. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Three Schiff-base-containing triazole derivatives have been synthesized and investigated by X-ray crystallography. Structural motifs (zigzag or linear chains) formed in the solid state are stabilized by C-Br‚‚‚N halogen bond interactions, while hydrogen bonds do not seem to play a significant role in the molecular self-organization of studied compounds. Quantum-chemical studies confirm that these interactions are sufficient to account for both the arrangement of structural motifs and very short Br‚‚‚N distances observed experimentally. It is also shown that Br‚‚‚N interactions can lead to generally shorter donor-acceptor distances than Cl‚‚‚N contacts.

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New p-0x0 di-iron N-methyltetraphenylporphyrin (MeTPP) species of formula [{(MeTPP)Fe}20](C104)2 and [(MeTPP)Fe-O-Fe(TPP)]C104 have been prepared by the reaction of (MeTPP)FeCI with silver perchlorate and characterized by Lr., visible, n.m.r., and Mossbauer spectroscopy and electrochemical measurements; the mechanism of formation of the di-iron complexes is briefly discussed.

Four new metal-organic polymeric complexes, {[Cu(mu-OH)(mu-ClPhtrz)][(H 2O)(BF 4)]} n ( 1), {[Cu(mu-OH)(mu-BrPhtrz)][(H 2O)(BF 4)]} n ( 2), {[Cu(mu-OH)(mu-ClPhtrz)(H 2O)](NO 3)} n ( 3), and {[Cu(mu-OH)(mu-BrPhtrz)(H 2O)](NO 3)} n ( 4) (ClPhtrz = N-[( E)-(4-chlorophenyl)methylidene]-4 H-1,2,4-triazol-4-amine; BrPhtrz = N-[( E)-(4-bromophenyl)methylidene]-4 H-1,2,4-triazol-4-amine), were synthesized in a reaction of substituted 1,2,4-triazole and various copper(II) salts in water/acetonitrile solutions. The structures of 1- 4 were characterized by single-crystal X-ray diffraction analysis. The Cu(II) ions are linked both by single N (1), N (2)-1,2,4-triazole and hydroxide bridges yielding one dimensional (1D) linear chain polymers. The tetragonally distorted octahedral geometry of copper atoms is completed alternately by two water and two BF 4 (-) anion molecules in 1 and 2 but solely by two water molecules in 3 and 4. Magnetic properties of all complexes were studied by variable temperature magnetic susceptibility measurements. The Cu(II) ions are strongly antiferromagnetically coupled with J = -419(1) cm (-1) ( 1), -412(2) cm (-1) ( 2), -391(3) cm (-1) ( 3), and -608(2) cm (-1) ( 4) (based on the Hamiltonian H = - J[ summation operator S i . S i+ 1]). The nature and the magnitude of the antiferromagnetic exchange were discussed on the basis of complementarity/countercomplementarity of the two competing bridges.

The direct reaction between [VCl(3)(thf)3] or [VO(OEt)3] and 2,2'-thiobis{4-(1,1,3,3-tetramethyl-butyl)phenol (tbopH(2)) leads to the formation of [V(2)(micro-tbop-kappa(3)O,S,O)2Cl(2)(CH(3)CN)(2)] (1).4CH(3)CN or [V(2)(micro-OEt)2(O)2(tbop-kappa(3)O,S,O)2] (2), respectively, in high yield. Compounds 1 and 2 were characterized by chemical and physical techniques including X-ray crystallography and variable temperature magnetic susceptibility studies (J = -29.1 cm(-1)) for 1. Complexes 1 and 2 were supported on MgCl2 and when activated with aluminium alkyls, were found to effectively polymerize ethene to produce polyethylene with a narrow molecular weight distribution M(w)/M(n) approximately 3.