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Michaele J Hardie

Publications and source records attributed to Michaele J Hardie.

17 recordsLinked to original sources
PubMed2006

Coordination and hydrogen bonded network structures of Cu(II) with mixed ligands: a hybrid hydrogen bonded material, an infinite sandwich arrangement, and a 3-D net.

Mixed-ligand Cu(II) complexes with deprotonated trimesic acid and phenanthroline-type ligands were synthesised by solvothermal methods to form 2-D infinite hexagonal hydrogen bonded structures with additional trimesic acid (H3tma) molecules. The complex [Cu(phendione)2(H2tma)2].2(H3tma).1.65(CF3CH2OH).2.5(H2O), where phendione = 1,10-phenanthroline-5,6-dione, has hydrogen bonded networks of [Cu(phendione)2(H2tma)2] complexes interspersed with layers of H3tma with a topologically identical hydrogen bonding network. Whereas in [Cu(1,10-phenanthroline)(H2tma)2]2.2(H3tma), a dimeric Cu(II) complex hydrogen bonds directly to additional H3tma molecules to form a three-layered 2-D network resembling an infinite sandwich. The synthesis and structures of simple Cu(II) complexes of the phendione ligand are also reported. One of these, [Cu(phendione)2Br2] shows a particularly polar packing arrangement.

Journal Article↗
PubMed2006

Tris(pyridylmethylamino)cyclotriguaiacylene cavitands: an investigation of the solution and solid-state behaviour of metallo-supramolecular cages and cavitand-based coordination polymers.

The synthesis of the three isomeric tris(pyridylmethylamino)cyclotriguaiacylene cavitands is reported, along with the crystal structures of the 2- and 4-pyridyl derivatives. The generality of a previously described [Ag(2){tris(3-pyridylmethylamino)cyclotriguaiacylene}(2)](2+) dimeric capsule motif and the [Ag(4){tris(4-pyridylmethylamino)cyclotriguaiacylene}(4)](4+) tetrahedron with several silver salts was confirmed in the solid state and the corresponding solution species were investigated by NMR spectroscopy. Host-guest interactions in these systems have been probed and these interactions are demonstrated to alter and influence the self-assembly outcome of the reaction. Notably, introduction of larger glutaronitrile guest molecules to the [Ag(4)L(4)](4+) tetrahedron system prevents formation of the tetrahedral structure, resulting instead in the formation of a 4.8(2) coordination network in the solid state. In the absence of templating acetonitrile guests in the [Ag(2)(3)(2)](2+) capsule system, formation of a cage-based one-dimensional coordination polymer is observed.

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PubMed2004

Interwoven 2-D coordination network prepared from the molecular host tris(isonicotinoyl)cyclotriguaiacylene and silver(I) cobalt(III) bis(dicarbollide).

A new 3-fold symmetric molecular host, tris(isonicotinoyl)cyclotriguaiacylene, has been synthesized from cyclotriguaiacylene and isonicotinoyl chloride hydrochloride in 70% yield. Its crystal structure shows dimerization of the host molecules into a capsule-like arrangement. When reacted with Ag[Co(C(2)B(9)H(11))(2)], the host forms a 1-D [ML(2)](n) coordination polymer, which assembles into a 2-D interwoven network through a similar dimerization of the host moieties around acetonitrile guests. Thus, the network structure represents an elegant example whereby the solid state structure of the building blocks is echoed in the resulting supramolecular assembly. The 2-D sheets are further stabilized by pi...pi stacking interactions between pyridyl donors of alternate 1-D coordination polymers.

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PubMed2004

Toward mimicking viral geometry with metal-organic systems.

Icosahedral and cuboctahedral arrangements of calixarenes, a nanometer-scale, spheroidal assembly of 12 calixarene molecules, can be manipulated in a highly controlled fashion. Previously, such assemblies were observed to favor placement of the calixarenes at the vertexes of an icosahedron. A supramolecular constraint is employed in order to enforce molecular alignment and produce a cuboctahedral arrangement. The internal volume of the cuboctahedron is approximately 30% greater than that of the icosahedron. Furthermore, in stark contrast to that of the icosahedral Platonic solid, the shell of the cuboctahedral Archimedean solid is porous.

Biomimetic Materials↗
PubMed2004

Bilayers, corrugated bilayers, and coordination polymers of p-sulfonatocalix[6]arene.

Exploration into the host-guest supramolecular chemistry of p-sulfonatocalix[6]arene with pyridine N-oxide and 4,4'-dipyridine N,N'-dioxide has resulted in the characterization of three new structural motifs with the calixarene in the "up-down" double partial cone conformation. Two are hydrogen-bonded network structures formed with pyridine N-oxide and either nickel or lanthanide metal counterions (1 and 2, respectively). Complex 1 displays host-guest interactions between pyridine N-oxide and the calixarene in the presence of hexaaquanickel(II) counterions. Complex 2 demonstrates selective coordination modes for different lanthanides involving the calixarene and pyridine N-oxide. The third structure, 3, is a coordination polymer which is formed with 4,4'-dipyridine N,N'-dioxide molecules which span a hydrophilic layer and join lanthanide/p-sulfonatocalix[6]arene fragments. Although complexes 1-3 all have the calixarene in the "up-down" double partial cone conformation, 1 and 3 form bilayer arrangements within the extended structures while 2 forms a previously unseen corrugated bilayer arrangement.

Calixarenes↗
PubMed2004

Building blocks for cyclotriveratrylene-based coordination networks.

The incorporation of three-fold symmetric organic host molecules into coordination polymers should allow for the construction of new and interesting network structures, capable of multiple inclusion behaviour. A range of new multi-dentate bridging ligands/molecular hosts have been prepared by appending nitrogen-containing heterocycles to either cyclotricatechylene, or cyclotriguaiacylene cores. These compounds were obtained in a single-step reaction from readily available precursors, with moderate to good yields, and characterised by a combination of NMR spectroscopy, mass spectrometry and elemental analysis. Two of the new compounds were characterised by X-ray crystallography, revealing different modes of self inclusion behaviour, which indicate the potential importance of [small pi]-donor stabilisation by CTV derivatives in host-guest chemistry.

Journal Article↗
PubMed2004

Lanthanide crown ether complexes of p-sulfonatocalix[5]arene.

Two types of arrays are formed in water involving aza-crown ethers, p-sulfonatocalix[5]arene and europium(III) ions. One is a co-ordination polymer connecting calixarenes, sodium ions and lanthanide ions based on "ferris wheel" moieties incorporating aza-18-crown-6 and sodium ions. The second structure is a host-guest arrangement with di-protonated diaza-18-crown-6 in the cavity of the calixarenes as part of secondary coordination spheres of aquated europium(iii) ions.

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PubMed2004

Coordination polymers with carborane anions: silver dinitrile complexes.

Crystalline materials have been isolated and characterized from mixing the silver carborane salts Ag(CB(11)H(12)) or Ag[Co(C(2)B(9)H(11))(2)] with nitrile ligands, either terminal acetonitrile or potentially bridging alkanedinitriles. Most of the complexes showed B-H...Ag interactions between the silver center and carborane anion. [Ag(acetonitrile)(2)(CB(11)H(12))] has a hexagonal network structure. [Ag(malonitrile)(2)(CB(11)H(12))] is a discrete dimeric complex, while [Ag(4)(succinonitrile)(5)(CB(11)H(12))(4)], [Ag(glutaronitrile)(2)][Co(C(2)B(9)H(12))(2)], and [Ag(glutaronitrile)[Co(C(2)B(9)H(11))(2)]] all show coordination chain structures. The carborane anions in [Ag(adiponitrile)[Co(C(2)B(9)H(11))(2)]] bridge between Ag centers to give a 3D CdSO(4)-related coordination polymer. The structure of [Ag(malonitrile)(2)](BF(4)) was also determined to have an unusual chiral diamondoid structure with a skewed 2-fold interpenetration.

Journal Article↗
PubMed2004

Group 1 coordination chains and hexagonal networks of host cyclotriveratrylene with halogenated monocarbaborane anions.

Halogenated carbaborane ions [CB(11)H(6)X(6)](-) in which X=Cl or Br have been combined with the host molecule cyclotriveratrylene (CTV) and Group 1 metal cations to give crystalline materials. The complexes [Na(ctv)(H(2)O)(CB(11)H(6)X(6))](CF(3)CH(2)OH) feature chiral Na-CTV coordination chains with complexation of the [CB(11)H(6)X(6)](-) ion by the Na(+) ion, together with the CTV molecular cavity. The coordination chains are hydrogen bonded together to give a puckered two-dimensional hexagonal grid structure. [K(ctv)(CB(11)H(6)Cl(6))(CF(3)CH(2)OH)(0.5)] is essentially isostructural. Complexes [Rb(ctv)(CB(11)H(6)Br(6))(H(2)O)] and [Cs(ctv)(CB(11)H(6)X(6))(CH(3)CN)] are coordination polymers with related distorted hexagonal grid structures. Use of N,N'-dimethylformamide (DMF) as a solvent results in an entirely different type of assembly, with [Na(2)(dmf)(4)(H(2)O)(2)(ctv)][(dmf)(0.5)(ctv)][CB(11)H(6)Br(6)](2) showing unusual [Na-mu-(dmf)-Na] bridges, and once again forming a distorted hexagonal coordination polymer.

Journal Article↗
PubMed2004

Tris[4-(1H-pyrazol-3-yl)-3-azabut-3-enyl]amine iron(II) diperchlorate monohydrate.

In the title complex, [Fe(C(18)H(24)N(10))](ClO(4))(2).H(2)O, the complex cation adopts a capped trigonal antiprismatic stereochemistry, with a long Fe-amine interaction [2.7468 (16) A]. The Fe centre in the asymmetric unit is fully high-spin at 100 K. Hydrogen bonding assembles dimeric units, which are then linked by further hydrogen bonding into chains running parallel to the crystallographic a axis.

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PubMed2003

Controlling the conformation and interplay of p-sulfonatocalix[6]arene as lanthanide crown ether complexes.

Control over the conformational flexibility of p-sulfonatocalix[6]arene in the solid state is possible in the presence of varied stoichiometric amounts of [18]crown-6 and selected lanthanide(III) chlorides. Complexes 1 and 2 have the calixarene in the elusive up-up double cone conformation, whilst complex 3 has the calixarene in the centrosymmetric up-down double partial cone conformation, whereby it acts as a divergent receptor. Complex 1 has a double molecular capsule arrangement which is composed of two p-sulfonatocalix[6]arenes shrouding two [18]crown-6 molecules, also with both coordinated and homoleptic aquated lanthanide ions around the hydrophilic sulfonate rims of the calixarenes. Complex 2 has a ferris wheel arrangement with one lanthanide metal centre coordinated to a sulfonate group and another coordinated to the crown ether whilst tethered to a sulfonate group of the calixarene. Complex 3 forms from a solution with large excess of [18]crown-6, and possesses a crown ether molecule in each of the partial cones and has homoleptic aquated lanthanide ions involved in a complicated hydrogen-bonding regime within the extended structure.

Journal Article↗
PubMed2003

Hydrogen-bonded superstructures of a small host molecule and lanthanide aquo ions.

Despite containing only relatively small molecular components, the structure of [Eu(H(2)O)(9)](1.5)(CTV)(6)(CH(3)CN)(5.5)(H(2)O)(7.5)[Co(C(2)B(9)H(11))(2)](4.5) (C(191)H(337.5)B(81)Co(4.5)Eu(1.5)N(5.5)O(57), a = 54.590(2) A, b = 37.5788(17) A, c = 31.8067(14) A, beta = 116.573(2) degrees, monoclinic, C2/c, Z = 8) is of an unusually large size and level of complexity, with an intricate hydrogen-bonding network formed between lanthanide aquo ions, water, and the small host molecule cyclotriveratrylene (=CTV). The 3D hydrogen-bonded network structure that results is unique and too complicated to apply the usual topological analysis. Instead a simplified model using structural subunits is described.

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