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Twonovel thiacalix[4]arene-based high-nuclearity cobalt clusters,[Na2Co24(BTC4A)6(PO4)6(HCOO)6(DMC)2(DMF)2(dma)4]·5DMF·9CH3OH (denoted as Na2@Co24, 1) and [KCo24(BTC4A)6(PO4)6(Cl)2(HCOO)4(DMF)8][KCo24(BTC4A)6(PO4)6(Cl)2(HCOO)6(DMF)4(CH3OH)2]·8DMF·23CH3OH (denotedas K@Co24, 2) (H4BTC4A = p-tert-butylthiacalix[4]arene, DMC = N,N'-dimethylcarbamic acid anion, dma = dimethylamine),have been solvothermally prepared and structurally characterized. Compounds 1and 2are each capped by sixCo4-BTC4A molecular building blocks (MBBs) and six phosphatelinkers and other different auxiliary anions, possessing an eicositetranuclearCo24core templated by alkali-metal cations. In essence, compound 1is templated by two Na+cationswith an attractive interaction in the center of the core, while 2is templated by one K+with a larger radius. Such differences "convert" an oval-shaped Co24disklike core in 1to a circular core in 2. Interestingly, 2contains both anionic and cationicKCo24cores, representing the largest cobalt aggregatesalt reported, to the best of our knowledge. In addition, magneticmeasurements of 1and 2were investigated, revealing the existence of antiferromagnetic interactions betweenthe magnetic CoIIcenters. [ABSTRACT FROM AUTHOR]

Four kite-like tetranuclear ZnIILNIII3 (Ln= Gd 1, Tb 2, Dy 3, Ho 4) clusters supported by p-ferf-butylthiacalix[4]arene (H4BTC4A) have been prepared under solvothermal conditions and structurally characterized by single crystal X-ray diffraction and powder X-ray diffraction (PXRD). In the structures of these four complexes, each of them is capped by two tail-to-tail p-ter£-butylthiacalix[4]arene molecules to form a bent sandwich-like unit The photoluminescent analyses reveal that the H4BTC4A is an efficient sensitizer for Tb3+ions in 2. The magnetic properties of complexes 1--4 are also investigated, in which complex 3 exhibits slow magnetization relaxation typical for single molecule magnets. [ABSTRACT FROM AUTHOR]

A series of discrete complexes, [Ni8(BTC4A)2(μ6-CO3)2(μ-CH3COO)4(dma)4]·H2O (1), [Ni8(BTC4A)2(μ6-CO3)2(μ-Cl)2(μ-HCOO)2(dma)4]·2DMF·2CH3CN (2), [Ni8(PTC4A)2 (μ6-CO3)2(μ-CH3COO)4(dma)4]·DMF (3), and [Ni8(PTC4A)2(μ6-CO3)2(μ-OH)(μ-HCOO)3 (dma)4] (4) (p-tert-butylthiacalix[4]arene = H4BTC4A, p-phenylthiacalix[4]arene = H4PTC4A, dma = dimethylamine, and DMF = N,N′-dimethylformamide), have been prepared under solvothermal conditions and structurally characterized by single-crystal X-ray diffraction analyses, powder XRD, and IR spectroscopy. These four complexes are stacked by dumbbell-like building blocks with one chairlike octanuclear-nickel(II) core, which is capped by two thiacalix[4]arene molecules and connected by two in situ generated carbonato anions and different auxiliary anions. This work implied that not only the solvent molecules but also the upper-rim groups of thiacalix[4]arenes have significant effects on the self-assembly of the dumbbell-like building blocks. The magnetic properties of complexes 1-4 were examined, indicating strong antiferromagnetic interactions between the nickel(II) ions in the temperature range of 50-300 K. [ABSTRACT FROM AUTHOR]

Two new compact molecular capsules of p-sulfonatothiacalix[4]arene with sodium ions have been synthesized by inducing suitable guest molecules, 1,2-bis(imidazol-1‘-yl)ethane or 2,2‘-bipyridine. Single-crystal X-ray diffraction analyses reveal that these supramolecular compounds possess open or close capsule conformations in a zigzag-like chain or a straight-line chain array. 1H NMR spectroscopic studies confirm that the above stable molecular capsules are present in solution. Their guest molecules in both compounds are well accommodated by p-sulfonatothiacalix[4]arene capsules via a variety of supramolecular interactions. [ABSTRACT FROM AUTHOR]

The article describes a copper-catalyzed method to construct C(sp2)-C(sp) bond via direct alkynylation of electron-deficient polyfluoroarenes with terminal alkynes. It states that O2 was used as an oxidant to enable the direct alkynylation of electron-deficient polyfluoroarenes to occur under mild conditions. It offers the scheme for the catalytic pathway of the direct alkynylation reaction.