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The ditopic organic molecule 3-(pyridin-4-yl)acetylacetone (HacacPy) acts as a pyridine-type ligand towards Hg X2 ( X = Cl, Br, I). The nature of the anion and the ligand-to-cation ratio dominate the outcome of the reaction. Two different coordination compounds form with HgCl2, namely a ligand-rich mononuclear complex, HgCl2(HacacPy)2, and a ligand-deficient one-dimensional chain polymer, [Hg( μ-Cl)2(HacacPy)]1∞, with five-coordinated HgII cations. Two compounds are also observed for HgBr2, a molecular complex isomorphous to the chloride derivative and a chain polymer with the composition [Hg( μ-Br)Br(HacacPy)]1∞, in which the cations are four-coordinated. The ligand-rich mononuclear and ligand-deficient polymeric chloride and bromide complexes may be interconverted via thermal degradation and mechanochemical synthesis. In contrast to the chloride and bromide compounds, the reaction product with HgI2 does not depend on the ligand-to-cation ratio but corresponds to [Hg( μ-I)I(HacacPy)]1∞, isomorphous to the bromide derivative. The N-coordinated HacacPy complexes could not be deprotonated and further crosslinked with a second cation. Synthesis of mixed-metal products could be achieved, however, by deprotonation of the acetylacetone moiety in HacacPy and formation of tris-chelated Fe(acacPy)3 and Al(acacPy)3 complexes in the first step. These mononuclear building blocks act as bridging poly(pyridine) ligands towards HgII halides and form two structure types. The first represents a one-dimensional ladder, with the tris(ligand) complexes acting as triconnected nodes and the HgII halides acting as linkers. In the alternative unprecedented product, both the tris(ligand) complexes and the [Hg X2( μ- X)Hg X] groups act as equivalent triconnected nodes. They form a uninodal two-dimensional coordination network with vertex symbol 4.82 and fes topology. [ABSTRACT FROM AUTHOR]

3-(Pyridin-4-yl)acetylacetone (HacacPy) acts as a pyridine-type ligand towards CdII and HgII halides. With CdBr2, the one-dimensional polymer [Cd(μ-Br)2(HacacPy)Cd(μ-Br)2(HacacPy)2]∞ is obtained in which five- and six-coordinated CdII cations alternate in the chain direction. Reaction of HacacPy with HgBr2 results in [Hg(μ-Br)Br(HacacPy)]∞, a polymer in which each HgII centre is tetracoordinated. In both compounds, each metal(II) cation is N-coordinated by at least one HacacPy ligand. Equimolar reaction between these CdII and HgII derivatives, either conducted in ethanol as solvent or via grinding in the solid state, leads to ligand redistribution and the formation of the well-ordered bimetallic polymer catena-poly[[bromidomercury(II)]-μ-bromido-[aquabis[4-hydroxy-3-(pyridin-4-yl)pent-3-en-2-one]cadmium(II)]-di-μ-bromido], [CdHgBr4(C10H11NO2)2(H2O)] n or [{HgBr}(μ-Br){(HacacPy)2Cd(H2O)}(μ-Br)2]∞. HgII and CdII cations alternate in the [100] direction. The HacacPy ligands do not bind to the HgII cations, which are tetracoordinated by three bridging and one terminal bromide ligand. The CdII centres adopt an only slightly distorted octahedral coordination. Three bromide ligands link them in a (2 + 1) pattern to neighbouring HgII atoms; two HacacPy ligands in a cis configuration, acting as N-atom donors, and a terminal aqua ligand complete the coordination sphere. Classical O-H...Br hydrogen bonds stabilize the polymeric chain. O-H...O hydrogen bonds between aqua H atoms and the uncoordinated carbonyl group of an HacacPy ligand in a neighbouring strand in the c direction link the chains into layers in the (010) plane. [ABSTRACT FROM AUTHOR]

3-(4-Pyridyl)-acetylacetone (HacacPy) acts as a pyridine-type ligand towards Cd X2 ( X = Cl, Br, I). Chain polymers with six-coordinated metal cations are obtained from CdCl2 and with alternating five- and six-coordinated Cd centers from CdBr2. In either case, the formation of these compounds does not depend on the precise stoichiometry. In contrast, two different reaction products form with the heavier congener CdI2, namely a ligand-rich molecular complex CdI2(HacacPy)2 and a ligand-deficient one-dimensional polymer [CdI2(HacacPy)]1∞. Interconversion between these two iodo derivatives is possible via thermal degradation and mechanochemical synthesis. The acetylacetone moiety in HacacPy may be deprotonated and chelated to FeIII, and the resulting complex Fe(acacPy)3 reacts analogously to a bridging polypyridine ligand towards the same Cd halides as the molecule HacacPy itself. With CdCl2 and CdBr2, isomorphous chain polymers are obtained in which the Cd cations adopt distorted octahedral coordination and one of the peripheric pyridyl groups remains uncoordinated. With CdI2, the iron complex acts as a -Fe(acacPy)3 bridge between tetrahedral Cd centers and gives rise to a ladder structure. [ABSTRACT FROM AUTHOR]