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A stimuli-responsive material with AND logic function was realized by modulating sensitive Cu-Cu interactions, which is quite different from traditional photoinduced electron transfer (PET) strategies. The obtained material not only gets rid of fluid media, but also displays nondestructive, high intensity optical signals and environmentally friendly performances.

Reaction of europium sulfate octahydrate with p-terphenyl-3,3″,5,5″-tetracarboxylic acid (H4ptptc) in a mixed solvent system has afforded three new coordination polymers formulated as {[Eu(ptptc)0.75(H2O)2]·0.5DMF·1.5H2O}n (1), {[Me2H2N]2 [Eu2(ptptc)2(H2O)(DMF)]·1.5DMF·7H2O}n (2), and {[Eu(Hptptc)(H2O)4]·0.5DMF·H2O}n (3). Complex 1 exhibits a three-dimensional (3D) metal-organic framework based on {Eu2(μ2-COO)2(COO)4}n chains, complex 2 shows a 3D metal-organic framework constructed by [Eu2(μ2-COO)2(COO)6](2-) dimetallic subunits, and complex 3 features a 2D layer architecture assembling to 3D framework through π···π interactions. All complexes exhibit the characteristic red luminescence of Eu(III) ion. The triplet state of ligand H4ptptc matches well with the emission level of Eu(III) ion, which allows the preparation of new optical materials with enhanced luminescence properties. The luminescence properties of these complexes are further studied in terms of their emission quantum yields, emission lifetimes, and the radiative/nonradiative rates.

Hydrothermal synthesis has afforded five divalent zinc coordination polymers containing 4-(4-carboxyphenyl)-2,2':6',2''-terpyridine (HL1) or its isomer 4-(4-carboxyphenyl)-2,2':4',4''-terpyridine (HL2), with or without the addition of auxiliary ligands, 1,3,5-benzenetricarboxylic acid (H3btc) and 1,4-benzenedicarboxylic acid (H2bdc). Their structures have been characterized by single crystal X-ray analyses and further characterized by infrared spectra, elemental analyses, powder X-ray diffraction, thermogravimetric analyses and photoluminescent spectra. Across this series, the π···π interactions have a dramatic impact on the self-assembly of these entanglement structures, in either case it can exert an important structure-directing role. In addition, the disposition of pyridine nitrogen atoms in ligands also plays a large role in structure direction in this system. Complex 1 is a 2D + 2D→3D inclined polycatenated coordination polymer based on the resulting array of 2D (6,3) layers constructed by 1D→2D π···π directed self-assembly. Complex 2 is assembled into a 3D framework by means of 1D + 1D→3D mutual interdigitation based on 1D→1D self-assembly driven by π···π stacking interactions. Complex 3 shows a 2D + 2D→3D interdigital network involving 2D + 2D→2D parallel interpenetrated and 2D + 2D→2D interdigital (4,4) layer motifs. Complex 4 displays a 2D + 2D→3D polythreaded framework based on a 2D (4,4) network comprised of alternating rings and rods. Complex 5 is a (3,4)-connected 3D framework with topology (4.8(2).10(3))(4.8(2)). In comparison with covalently connected entanglements, such π···π directing self-assembly of entanglements are far less explored, especially, polycatenane based on 1D chain motifs and polythread based on 2D layer motifs are rarely reported. Furthermore, the luminescent properties of complexes 1-5 at room temperature have also been studied in detail herein.

Four kite-like tetranuclear Zn(II)Ln(III)3 (Ln= Gd 1, Tb 2, Dy 3, Ho 4) clusters supported by p-tert-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-tert-butylthiacalix[4]arene molecules to form a bent sandwich-like unit. The photoluminescent analyses reveal that the H4BTC4A is an efficient sensitizer for Tb(3+) 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.

The reaction of AgNO 3 , NaS 2 CNEt 2 and H 2 NPhSH in the presence of (Ph 3 P) 3 CuCl in MeOH gave a polynuclear silver cluster compound, [Ag 11 (μ 5 -S)(μ 4 -S 2 CNEt 2 ) 6 (μ 3 -S 2 CNEt 2 ) 3 ]. A cleavage of the S-C bond and release of S 2 from 2-aminothiophenal occurred in the reaction. The core of Ag 11 S consists of five layers: Ag, 3Ag, 3AgS, 3Ag and Ag. The average Ag-Ag and Ag-S c (S c for core sulfur atom) distances are 3.046 and 2.513 , respectively. Copyright © 1996 Elsevier Science Ltd

By the reactions of Pd 2+ , 1,1-dithiolate [SC 6 H 3 (CH 3 )S 2− , SCH 2 CH 2 S 2− or SCH 2 CH (CH 3 )S 2− ] or thiolate (HOC 6 H 4 S − ) and PR 3 (R = Ph, Et) in MeOH, the complexes [Pd(tdt)(PPh 3 ) 2 ] ( 1 ), [Pd 2 (edt) 2 (PPh 3 ) 2 ] ( 2 ), [Pd 2 (pdt) 2 (PPh 3 ) 2 ] ( 3 ), [Pd 2 (edt) 2 (PEt 3 ) 2 ] ( 4 ), [Pd 2 (pdt) 2 (PEt 3 ) 2 ] ( 5 ), [Pd 2 (Hmp) 2 (PPh 3 ) 2 Cl 2 ] ( 6 ) and [Pd 2 (tdt) 2 (PEt 3 ) 2 ] ( 7 ) (tdt = 1,2-toluenedithiolateedt = 1,2-ethanedithiol, pdt = 1,2-propanedithiol and mp = mercaptophenol) were prepared and analysed by X-ray diffraction. All palladium atoms are tetra-coordinated with distorted square-planar geometry of phosphorus and/or sulfur atoms. The reaction mechanism of Pd 2+ , 1,2-dithiolate and PR 3 (R = Et, Ph) is discussed.

The exchange coupling of cobalt atoms in the mixed-valence tetracobalt complex with 2-mercaptopyridine-N-oxide (mpo) ligands, [Na3Co4(mpo)8(μ3-O2 (DMF)4]Br·DMF, has been examined by fitting the variable-temperature magnetic susceptibility based on the Heisenberg theory. The results show that the complex exhibits anti-ferromagnetic coupling between CoII and CoIII sites with a coupling constant J of −20.5 cm−1. Uncertainty of the J value obtained is surveyed by an error analysis procedure.

The title compound, octa-μ 3 -thio-hexakis(triphenylphosphine)-octahedro-hexacobalt-triphenylphosphine-1,2-dichloroethane-water (1/2/2/1), [Co 6 S 8 (C 18 H 15 P) 6 ].2C 18 H 15 P.2C 2 H 4 Cl 2 .H 2 O, was prepared by the reaction of CoCl(PPh 3 ) 3 with Na(mpo) (mpo = 2-mercaptopyridine N-oxide) or NaS t Bu. The molecular structure consists of discrete cluster units interspersed with molecules of free triphenylphosphine and solvent. The neutral cluster contains a slightly distorted Co 6 octahedron with each triangular face symmetrically capped by a μ 3 -S ligand. The molecular structure possesses a crystallographic inversion centre. The average Co-Co, Co-S and Co-P bond distances are 2.87 (6), 2.24(1) and 2.162(7)A, respectively. The hexacobalt sulfide cluster compound was formed via the capture of S atoms from thiolate reactants.

A new compound [Na3Co4(μ3-O)2(mpo)8(DMF)4]Br·2DMF (1) was prepared by reacting CoBr(PPh3)3 and Nampo (mpo = 2-mercaptopyridine-N-oxide), and structurally characterized by X-ray diffraction methods. The title compound crystallizes in the triclinic space group P1 with a = 13.393(7), b = 14.00(1), c = 13.029(4) A, α = 92.29(4), β = 110.56(3), γ = 115.32(4)°, V = 2015(2) A3, Z = 1 and R (Rw) = 0.047 (0.053) for 1820 reflections (I > 3 σ(I)). The complex contains four cobalt atoms in the form of a square plane with indirect metal-metal bonds. Each Co atom is coordinated by two bidentate mpo ligands with StOb-D and StOb-T coordination modes, respectively. Two Co2(mpo)4O groups each bridged by μ3-O in the Na3Co4 core are linked by Na3 through the oxygen atoms of the mpo ligands and the bridging μ3-O atoms to form a dumbbell-like structure. The structure of the symmetric tetracobalt cation [Na3Co4(μ3-O)2(mpo)8(DMF)4]+ possesses a crystallographic inversion center through the Na(1) atom. The relevance of the spectroscopic and magnetic properties to the structure of 1 is also discussed.

The mixed polymeric cobalt compound [Co3(SCH2CH2S)3(PEt3)3]2[Co2Cl4(µ-O2SEt2)2]1 containing two trimers and one dimer was isolated from the reaction of [CoCl(PEt3)3] with disodium ethane-1,2-dithiolate in 1,2-dichloroethane. It is monoclinic and crystallizes in space group P21/n, with a= 12.481(7), b= 15.70(2), c= 25.84(2)A, β= 97.85(5)° and Z= 2 from 2436 reflections with I > 3.50σ(I), final R= 0.062. X-Ray diffraction established that the two cobalt atoms in the dimer are linked via the oxygen atoms of the diethyl sulfone forming the eight-membered Co2O4S2 ring with a crystallographic inversion centre through the whole dimer. The observed cleavage of the dithiolate C–S bond together with the formation of the bridging diethyl sulfone are discussed. In the trimer of 1, the Co3 isosceles triangle is capped by two bidentate SCH2CH2S2– ligands on either side of the plane with the sulfur atoms bridging the two long Co–Co bonds, while the short Co–Co bond is bridged by the third SCH2CH2S2– ligand. Considering the framework of the Co3P3(SCH2CH2S)3 unit only, there is a pseudo mirror-image plane passing through the Co3P3 plane which bisects the C(31)–C(32) bond. The 1H NMR spectrum of compound 1 demonstrates the retention of the solid-state structure of the trinuclear species in chloroform solution.

Induced by different anions, two different polycatenanes constructed from Ag(6)L(4) units with different conformations have been prepared. Intermediates Ag(6)L(4) and Ag(5)L(4) are observed to participate in interlocking, and the related possible self-assembly routes are also presented.

A novel flexible multisite cyclotetraphosphazene ligand, octakis(4-pyridylamino)cyclotetraphosphazene (OPCP), was synthesized through a new method, and it represents the first fully substituted pyridylaminocylcophosphazene ligand with eight coordinating arms. Self-assemblies of OPCP and different transition metal ions result in three novel 3D coordination polymers, in which the Cd(II) complex exhibits a quite strong blue emission.

A metal-organic framework, with chiral 4(1) In(OH)(CO(2))(2) helix chains, exhibits a high CO(2) uptake under ambient conditions and outstanding selective separations of CO(2) from CH(4) or N(2). Its high stability toward humidity or even boiling water is confirmed by PXRD method.

A series of discrete complexes, [Ni(8)(BTC4A)(2)(μ(6)-CO(3))(2)(μ-CH(3)COO)(4)(dma)(4)]·H(2)O (1), [Ni(8)(BTC4A)(2)(μ(6)-CO(3))(2)(μ-Cl)(2)(μ-HCOO)(2)(dma)(4)]·2DMF·2CH(3)CN (2), [Ni(8)(PTC4A)(2) (μ(6)-CO(3))(2)(μ-CH(3)COO)(4)(dma)(4)]·DMF (3), and [Ni(8)(PTC4A)(2)(μ(6)-CO(3))(2)(μ-OH)(μ-HCOO)(3) (dma)(4)] (4) (p-tert-butylthiacalix[4]arene = H(4)BTC4A, p-phenylthiacalix[4]arene = H(4)PTC4A, 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.

Three new compounds, CuL, CuL', and Cu(2)O(2)L''(2) (H(2)L = 3'-[(E)-{[(1S,2S)-2-aminocyclohexyl]imino}methyl]-4'-hydroxy-4-biphenylcarboxlic acid, H(2)L' = 3'-[(E)-{[(1S,2S)-2-aminocyclohexyl]imino}methyl]-4'-hydroxy-5'-nitro-4-biphenylcarboxlic acid, H(2)L'' = 3'-(N,N-dimethylamino methyl)-4'-hydroxy-4-biphenylcarboxlic acid), were selectively synthesized through a controlled in situ ligand reaction system mediated by copper(II) nitrate and H(2)L. Selective nitration was achieved by using different solvent mixtures under relatively mild conditions, and an interesting and economical reductive amination system in DMF/EtOH/H(2) O was also found. All crystal structures were determined by single-crystal X-ray diffraction analysis. Both CuL and CuL' display chiral 1D chain structures, whereas Cu(2)O(2)L''(2) possesses a structure with 13×16 A channels and a free volume of 41.4 %. The possible mechanisms involved in this in situ ligand-controlled reaction system are discussed in detail.

Two novel 2D sheet-like complexes 1 and 2 have been prepared by reaction of p-sulfonatothiacalix[4]arene (TC4AS) with main-group metal ions (lead(II) or barium(II)) and 4,4′-bipyridine-N,N′-dioxide (4,4′-bpno). In both complexes 1 and 2, TC4AS molecules prefer 1,2-alternate conformation, forming 2D sheet-like layers in the presence of divalent ions and 4,4′-bpno ligand. The layers extend to 3D architectures via strong hydrogen bonding interactions. In addition, complexes 1 and 2 are thermally stable up to ca. 335 and 305 °C, respectively. It seems that the strong hydrogen bonds between the sheet-like layers impart the extraordinarily high degrees of stability to the structures. Further analysis indicates that complexes 1 and 2 are significantly different: (a) the divalent ions have different coordination environments due to the nature of the different ions; (b) TC4AS within complexes 1 and 2 connects to four Pb(II) or six Ba(II) ions, respectively; (c) 4,4′-bpno shows different connection modes; (d) in the solid state, complex 1 exhibits intense orange luminescence with triexponential decays, while complex 2 does not exhibit any obvious luminescence at cryogenic temperatures.

A novel microporous polyhedral framework [Zn(6)(btb)(4)(4,4'-bipy)(3)(dmf)(55)(H(2)O)(32)] with high surface area has been designed and synthesized, which shows high multigas-uptake capacity via supercritical carbon dioxide (SCD) activation.

As a new member of the water-soluble calixarene family, p-sulfonatothiacalix[4]arene possesses unique properties resulting from its inherent structural characteristics. In our recent research, we have investigated the self-assembly of bowl-like p-sulfonatothiacalix[4]arenes with or without transition-metal ions in the presence of suitable guests. We have obtained a series of compounds with different structural motifs, such as capsules, tetranuclear clusters, and molecular clefts. In addition, p-sulfonatothiacalix[4]arenes show good inclusion abilities and can capture different guests by utilizing their hydrophobic cavities through supramolecular interactions. Even when a cone-like conformation is fixed, the p-sulfonatothiacalix[4]arene can also splay its opposite aromatic rings apart to adjust its cone-like conformations from C4v to C2v and even lower symmetries. All of these show that it is a good candidate for the research of inclusion phenomena. © 2009 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 9: 155–168; 2009: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.200800033

Through an in situ hydrolysis reaction of the bishydrazone ligand H4L1 [H4L1=(HOC6H4)CH=NNHCO(C5H3N)CONHN[double bond, length as m-dash]CH(C6H4OH)], in the presence of Fe(III) ions, an interwoven trigonal metallamacrocycle [Fe3L3(H2O)3].9H2O () [H3L=(HOC6H4)CH=NNHCO(C5H3N)CO2H] containing unusually double-layered capsule-like water hexamers was obtained and characterized by elemental analysis, FT-IR, TGA, ESI-MS and X-ray crystallography.

Four types of cobalt-lanthanide heterometallic compounds based on metalloligand Co(2,5-pydc)(3) (3-) (2,5-H(2)pydc=pyridine-2,5-dicarboxylate acid), [Ln(2)Co(2)(2,5-pydc)(6)(H(2)O)(4)](n) 2n H(2)O (1) (Ln=Tb, Dy for 1 a, 1 b respectively), [Tb(2)Co(2)(2,5-pydc)(6)(H(2)O)(4)](n)3n H(2)O (2), [Tb(2)Co(2)(2,5-pydc)(6)(H(2)O)(9)](n)4n H(2)O (3), and [LaCo(2,5-pydc)(3)(H(2)O)(2)](n)2n H(2)O (4) have been synthesized. Compound 1 has a layer structure with well-isolated carboxylate-bridged Ln(3+) chains, compound 2 is a three-dimensional (3D) porous network with Tb(3+) chains that are also well isolated and carboxylate bridged, 3 is a layer structure based on dinuclear units, and 4 is a 3D network with boron nitride (BN) topology. DC magnetic studies reveal ferromagnetic coupling in all the carboxylate-bridged Ln(3+) chains in 1 a, 1 b, and 2. Compared to the silence of the out-of-phase ac susceptibility of 2, above 1.9 K the magnetic relaxation behavior of both 1 a and 1 b is slow like that of a single-chain magnet.

The reaction of Co(PPh3)3Cl and K2S2C=C(CN)2 in a 1:1 molar ratio in MeCN led to S-C bond cleavage of [S2C=C(CN)2]2− and allowed isolation of a pentanuclear cobalt cluster compound [Co5(μ3-S)4{μ-SC=C(CN)2}2(PPh3)4] 1 and an octanuclear cobalt cluster compound with mixed Co(I) and Co(II), (PPh4)[Co8(μ4-S)6Br2Cl2(PPh3)4] 2; the core in 1 is a highly distorted Co5 trigonal bipyramid, while that in 2 is a Co8 cube.

The title compound, [Ni(C 6 H 5 S) 2 (C 12 H 27 P) 2 ], was isolated from the reaction of NiCl 2 .6H 2 O, NaSPh and P n Bu 3 in MeOH. The molecule possesses a crystallographic inversion center at the Ni atom which is fourfold coordinated by two P and two S atoms with almost square-planar geometry. The Ni-S and Ni-P distances are 2.217 (2) and 2.245 (2) A, respectively.

0.8649 (3) 0.5317 (2) 0.0601 (9) 0.8705 (3) 0.5823 (3) 0.0764 (12) 0.7908 (3) 0.6254 (3) 0.0730 (11) 0.7059 (3) 0.6178 (2) 0.0613 (9) 0.6968 (2) 0.5686 (2) 0.0487 (8) 0.8953 (2) 0.4052 (2) 0.0492 (8) 0.9648 (2) 0.4486 (3) 0.0568 (9) 1.0454 (3) 0.4002 (3) 0.0734 (12) 1.0583 (3) 0.3143 (4) 0.0797 (13) 0.9927 (3) 0.2717 (3) 0.0733 (11) 0.9117 (3) 0.3179 (2) 0.0590 (9) 0.7715 (3) 0.3957 (2) 0.0598 (9) 0.5997 (2) 0.5647 (2) 0.0643 (10) 0.9598 (3) 0.5425 (3) 0.0778 (12)

Colorless [Au{C(NHMe) 2 } 2 ]X.H 2 O (X = Cl or Br) crystallize as dimers with Au...Au separations of 3.1231(3) A (Cl salt) and 3.1297(4) A (Br salt) between the linear, two-coordinate cations, and there is no direct interaction of Au(I) with the halide ions which are hydrogen bonded to ligand N-H groups and the water molecules. The luminescence of these dimers occurs at higher energy than that observed in extended chains of the same cation in the corresponding (PF 6 ) - and (BF 4 ) - salts and shows the important effects of aggregation on the observed luminescence.

The unusual luminescence behavior of the two-coordinate gold(I) carbene complex, [Au[C(NHMe)(2)](2)](PF(6)) x 0.5(acetone), is reported. Upon freezing in a liquid N(2) bath, the colorless, nonluminescent solutions of [Au[C(NHMe)(2)](2)](PF(6)) x 0.5(acetone) become intensely luminescent. Strikingly, the colors of the emission differ in different solvents and appear only after the solvent has frozen. Solid [Au[C(NHMe)(2)](2)](PF(6)) x 0.5(acetone) is also luminescent, and the luminescence is attributed to the formation of extended chains of gold(I) centers that are connected through aurophilic attractions. Crystallographic studies of [Au[C(NHMe)(2)](2)](PF(6)) x 0.5(acetone) and [Au[C(NHMe)(2)](2)](BF(4)), which is also luminescent, reveal that both involve extended chains of cations and that the anions are hydrogen bonded to the cations through cation N-H groups. However, these chains differ in the Au...Au separations in each and in the carbene ligand orientations. In contrast, [Au[C(NMe(2))(NHMe)](2)](PF(6)) forms a colorless, nonluminescent solid, and in that solid there are no Au...Au interactions, a factor which supports the contention that aggregated species are responsible for the luminescence of [Au[C(NHMe)(2)](2)](PF(6)) x 0.5(acetone) in the solid state and in frozen solutions.

The low-valence cobalt cluster [Co 7 (μ 4 -S) 3 (μ 3 -S) 3 (PPh 3 ) 6 Br] ( 1 ) was isolated from the reaction of Co(PPh 3 ) 3 Br with Na 2 edt in ethylene chloride. The skeleton [Co 7 S 6 ] + of 1 can be represented as a monocapped-prismane formed by the addition of the capping atom cobalt to the prismane [Co 6 S 6 ] as shown by X-ray single-crystal structure analysis. In this reaction the S 2− ion is derived from the edt 2− ion through cleavage of the CS bond, and incorporated into the building process.

Two indium–organic framework isomers, namely [Me2NH2][In(BPDC)2] (InOF-3) and [MeNH3][In(BPDC)2] (InOF-4), have been solvothermally prepared from a biphenyl-3,3′-dicarboxylate ligand (H2BPDC) with changeable conformation, and feature skeletal frameworks with equivalent chemical formulae. For the 2D close-packing InOF-3, each 3-connected [In(O2CR)4] node connects to 3 others through syn-BPDC2− ligands, leading to a 3-connected uninodal layer with a point symbol of {63}. For the 3D microporous InOF-4, the framework is assembled from [In(O2CR)4] nodes bridged by dicarboxylate ligands in the anti- fashion. Careful examination of the structure shows that InOF-4 is a 4-fold interpenetrating network and topologically adopts a diamond-like 4-connected uninodal net with a point symbol of {66}. More importantly, the theoretical calculations and the experimental single component gas uptake measurements reveal that the 3D porous InOF-4 has a better low pressure gas storage capacity than its 2D framework isomer InOF-3, with a saturated N2 uptake of 168.2 cm3 g−1 at 77 K and H2 uptake capacities of up to 126.5 cm3 g−1 (1.13 wt%) at 77 K and 1.0 bar, and 98.1 cm3 g−1 (0.88 wt%) at 87 K and 1.0 bar. Finally, the IAST calculations show us that both microporous materials have an outstanding low-pressure selectivity between CO2 and N2, probably due to their intrinsic structural characteristics.

The dioxovanadium(IV) complexes with pida(4)(-) ligands (H(4)pida) = N-(phosphonomethyl)iminodiacetic acid), Na(4)[V(2)O(2){(O)(2)P(O)CH(2)N(CH(2)COO)(2)}(2)].10H(2)O (1) and Na(8)[V(2)O(2){(O)(2)P(O)CH(2)N(CH(2)COO)(2)}(2)](2).16H(2)O (2), were isolated from reactions of H(4)pida with either oxovanadium(V) (i.e., NaVO(3)) or oxovanadium(IV) precursors within the pH range of 2-8. The structures of complexes 1 and 2 were investigated by X-ray diffraction methods and in contrast to expectation were both found to be dinuclear. Complex 1 crystallized in the monoclinic system: P2(1)/n, a = 10.5632(1) Å, b = 11.1868(1) Å, c = 12.6921(1) Å, beta = 106.45 degrees, V = 1438.44(2) Å(3), Z = 4, and R (wR2) = 0.0781 (0.2017). Complex 2 crystallized in the monoclinic system P2(1)/c: a = 13.9822(2) Å, b = 11.1888(2) Å, c = 18.6519(3) Å, beta = 100.88 degrees, V = 2865.51(8) Å(3), Z = 4, and R (wR2) = 0.046 (0.125). Both complexes 1 and 2 have similar dimeric frameworks where two vanadium centers are linked by two phosphonate groups of two pida(4)(-) ligands (quadridentate binucleating), bridging through their four oxygen atoms to form a V(2)O(4)P(2) eight-membered ring which possesses a crystallographic inversion center. In contrast to their solid-state features, in aqueous solution both dinuclear crystalline compounds immediately dissociate to monomeric species, as observed by EPR and UV/vis spectroscopy. Both solution-state EPR and NMR spectroscopy confirmed that redox chemistry is involved in the reaction between vanadate and H(4)pida. Studies in mixed solvent systems showed that the dinuclear complex would remain intact in the presence of sufficient organic solvent. In the absence of oxygen the mononuclear and the dinuclear complexes will reversibly interconvert, whereas, in the presence of oxygen, the complexes will oxidize. These studies document the existence of higher oligomeric vanadium compounds and surprisingly, in general, lend credibility to several emerging mechanistic proposals involving oligomeric species of vanadium compounds in catalytic processes.

The studies of an underexplored synthetic reagent, VO(2)(acac) (Hacac = acetylacetone) and semirational strategies for the formation of a complete series of simple vanadium(V) alkoxide clusters in alcohol-containing solvents. The neutral mono-, di-, tri-, and tetranuclear oxovanadium(V) complexes [V(2)O(2)(mgr;-OCH(3))(2)(acac)(2)(OCH(3))(2)] (1), [V(4)O(4)(mgr;-O)(2)(mgr;-OCH(3))(2)(mgr;(3)-OCH(3))(2)(acac)(2)(OCH(3))(2)].2CH(3)CN (2), [V(4)O(4)(mgr;-O)(2)(mgr;-OCH(3))(2)(mgr;(3)-OCH(3))(2)(acac)(2)(OCH(3))(2)] (3), [V(3)O(3){mgr;,mgr;-(OCH(2))(3)CCH(3)}(2)(acac)(2)(OR)] (R = CH(3) (4), C(2)H(5) (5)), and cis-[VO(OCH(CH(3))(2))(acac)(2)] (6) with alkoxide and acac(-) ligands were obtained by reaction of VO(2)(acac) with a monoalcohol and/or a tridentate alcohol. The structures of complexes 1-3, 5, and 6 were determined by X-ray diffraction methods. Complex 1 crystallized in the monoclinic system, P2(1)/n, with a = 7.8668(5) Å, b = 15.1037(9) Å, c = 8.5879(5) Å, beta = 106.150(1) degrees, V = 980.1(1) Å(3), Z = 2, and R (wR2) = 0.040 (0.121). Complex 2 crystallized in the monoclinic system, P2(1)/n, with a = 8.531(2) Å, b = 14.703(3) Å, c = 12.574(2) Å, beta = 95.95(2) degrees, V = 1568.7(5) Å(3), Z = 2, and R (wR2) = 0.052 (0.127). Complex 3 crystallized in the triclinic system, Ponemacr;, with a = 8.5100(8) Å, b = 8.9714(8) Å, c = 10.3708(10) Å, alpha = 110.761(1) degrees, beta = 103.104(1) degrees, gamma = 100.155(1) degrees, V = 691.85(11) Å(3), Z = 1, and R (wR2) = 0.040 (0.105). Complex 5 crystallized in the monoclinic system, P2(1)/n, with a = 14.019(2) Å, b = 11.171(2) Å, c = 19.447(3) Å, beta = 109.18(1) degrees, V = 2876.5(8) Å(3), Z = 4, and R (wR2) = 0.062 (0.157). Complex 6 crystallized in the monoclinic system, P2(1)/n, with a = 15.0023(8) Å, b = 8.1368(1) Å, c = 26.5598(2) Å, beta = 95.744(1) degrees, V = 3225.89(8) Å(3), Z = 8, and R (wR2) = 0.060 (0.154). Complex 1 is a discrete, centrosymmetric dimer in which two vanadium atoms are bridged by two methoxide ligands. Compound 2 contains a V(4)O(4) eight-membered ring with bothmgr;-oxo andmgr;-alkoxo bridging ligands; the ring is capped above and below by two triply bridging methoxo ligands. Compound 3 has the same structure as 2. The three vanadium atoms in complex 5 are linked by four bridging oxygen atoms from two tridentate thme(3)(-) ligands to form a V(3)O(4) chain in which V-O bonds alternate in length. The V-O(isopropoxo) bond in 6 is cis to V=O, and the V-O(acac) bond trans to the oxo group is relatively long. The V(2)O(2) rings of complex 1 and the mononuclear 1:2 complex can be considered to be the basic building block of the trinuclear complexes 4 and 5 and the tetranuclear complex 2, acting to extend the vanadium-oxide framework. (51)V and (1)H NMR spectroscopic studies of the solution state of complexes 1-6 revealed dramatic differences in structural and hydrolytic stability of these complexes. Compounds 1 and 3 only remained intact at low temperature in CDCl(3) solution, whereas the mononuclear compound 6 could remain at ambient temperature for approximately 10 h. Compound 4 only maintained its solid-state structure at low temperature in CDCl(3) solution, whereas compound 5 was significantly more stable. The structural integrity of oligomeric vanadium-oxygen frameworks increased significantly when the coordinating alkoxide group showed more resistance to exchange reactions than the methoxide group. The solid state and solution properties of this new group of complexes not only testify to the versatility of VO(2)(acac) as a vanadium(V) precursor but also raise questions relating to solution structure and properties of related vanadium complexes with insulin-mimetic properties and catalytic properties.

The title compound has been obtained by treating CoCl(PPh3)3 with excess Li2S in chloroform. An X-ray diffraction study established that the structure of the Co7S6 core can be viewed as a monocapped-prismane or a perfect cube [Co8S6] missing a corner cobalt, which possesses a crystallographic C3 axis coincident with the Co(1)P bond.

A porous metal-organic framework with high surface area was designedly synthesized, in which polyhedral cages and one-dimensional channels coexist. It shows a total gravimetric H2 uptake of 11.35 wt% at 77 K and 90 bar and a total CH4 uptake of 305.07 cm(3) g(-1) at 298 K and 35 bar.

Tetranuclear vanadium complexes with alkoxy ligands, [V(4)O(4){mgr;,mgr;,mgr;(3)-(OCH(2))(3)CCH(3)}(2)(OCH(3))(6)] (1) and [V(4)O(4){mgr;-(OCH(2))(3)CCH(3)}{mgr;,mgr;(3)-(OCH(2))(3)CCH(3)}{mgr;,mgr;,mgr;(3)-(OCH(2))(3)CCH(3)}(OR)(3)] (R = C(2)H(5) (2), R = CH(CH(3))(2) (3), R = CH(3) (4)), were synthesized by reacting VO(OR)(3) and H(3)thme (H(3)thme = 1,1,1-tris(hydroxymethyl)ethane) in alcohol. Complex 1 crystallized in the monoclinic space group P2(1)/n with a = 9.646(4) Å, b = 11.502(3) Å, c = 11.960(3) Å, beta = 90.20(3) degrees, V = 1326.9 (7) Å(3), Z = 2 and R (wR(2)) = 0.045 (0.143). Complex 2 also crystallized in the monoclinic space group P2(1)/n with a = 8.290(8) Å, b = 12.237(2) Å, c = 29.118(4) Å, beta = 89.455(9) degrees, V = 2954(3) Å(3), Z = 4, and R(wR(2)) = 0.049 (0.126). Both 1 and 2 are neutral, discrete complexes possessing a common [V(4)O(16)](12)(-) core, which consists of four vanadium(V) atoms chelated by two (1) or three (2) tridentate thme(3)(-) ligands and by six (1) or three (2) RO(-) groups. Compound 1 exhibits a crystallographically required inversion center; in contrast, complex 2 exhibits no crystallographically imposed symmetry, and its three trialkoxy ligands each coordinate differently (one thme(3)(-) is coordinated in a new coordination mode with the oxygens in a terminal, doubly-bridging and triply-bridging mode). Both compounds 1 and 2 maintain their structures in solution, although compound 1 also forms a second minor species upon dissolution. Sequential exchanges of the RO(-) groups in complexes 2 and 3 were investigated by (51)V and (1)H NMR spectroscopy. For example, [V(4)O(4)(thme)(3)(OC(2)H(5))(3)] will react with CH(3)OH to generate [V(4)O(4)(thme)(3)(OCH(3))(3)] (4). These reactions were found to be reversible. The time scale of the alcohol exchange reactions were found to vary depending on the vanadium center that is undergoing the exchange.

The dimeric title mol­ecule, [Ag2Br2(C2H3N)2(C18H15P)2], has crystallographic inversion symmetry. The two bridging Ag—Br lengths are similar, at 2.7301 (6) and 2.7284 (7) A.

Two novel 3D porous metal–organic frameworks, {[Zn2(bpt)(btc)]·4H2O}n (1) and {[Cd2(bpt)(btc)(H2O)]·(DMA)2}n (2) (DMA = N,N-dimethylacetamide), were prepared based on 3,5-bis(pyrazinyl)-1,2,4-trizole (Hbpt) with the auxiliary ligand 1,3,5-benzenetricarboxylic acid (H3btc). Complex 1 could be described as a (3,6)-connected binodal 3D network with rutile topology and Schlafli symbol of (4.62)2(42.610.83), where its coordination framework exhibits a high thermal stability up to 420 °C as well as excellent boiling-water resistance. Complex 2 shows a (3,6,8)-connected trinodal 3D framework with a Schlafli symbol of (4.62)2(414.612.82)(44.610.8), which has not been reported previously. Interestingly, the gas-adsorption investigation discloses that complex 1 possesses a high enthalpy of H2 adsorption (9.6 kJ mol−1). Intensive solid-state fluorescence spectra of complexes 1 and 2 have also been determined.

Two classical metal clusters, CuI4I4 and CuI6S6, are introduced as functional connecting nodes to construct a novel multi-metal-cluster MOF [(CuI4I4)3(CuI6)2(3-ptt)12]n·24nDEF·12nH2O (1) that incorporate their inherent luminescent properties, induced by their respective metal–metal interactions. These two distinct clusters are combined together for the first time to perform as functional luminophores that display unusual dual emission with both thermochromic luminescence and near-infrared (NIR) character.

Hydrothermal reaction of cadmium salt, 3,3′,4,4′-diphenylsulfonetetracarboxylic acid (H4dpstc) and 1,10-phenanthroline (phen) under different pH conditions have afforded four novel supramolecular complexes, in which the pH value of the reaction solution plays a crucial structure-directing role. [Cd(H2dpstc)(phen)]n (1) formed in a neutral reaction environment exhibits a 1D infinite chain structure containing partially deprotonated H2dpstc2− as the H-bond donors and acceptors. Whereas [Cd2(dpstc)(phen)2]n·4.5nH2O (2), [Cd2(dpstc)(phen)2]n·nH2O (3) and [Cd2(dpstc)(phen)4(H2O)2]·6H2O (4) contain fully deprotonated dpstc4− ligands due to the alkaline reaction conditions. Complex 2 possesses a unique 2D layered structure with 1D channels. The most striking feature of 2 is that its 2D holed (4,4)-water-net is constructed from hexameric water clusters and two types of dimeric water clusters. Surprisingly, the water net and the metal–organic skeleton are interpenetrated to form a fascinating 3D metal–organic–water supramolecular architecture. A further increase of the pH value leads to another 2D layered framework of 3 containing dumbbell-shaped rings as subunits. Reaction at a strongly alkaline solution leads to a discrete molecule of 4. Meanwhile solid-state properties such as thermal stability and the photoluminescence properties at room temperature for these complexes have also been systematically investigated.

A novel strategy is provided in this paper to design multi-stimuli-responsive luminescent materials by taking a multi-responsive chromophore which responds to multiple environmental stimuli instead of constructing multi-chromophore systems. Herein, we have successfully prepared a tri-stimuli-responsive luminescent material, [Cu4I4(4-dpda)4] (1), with reversible and independent thermochromism, mechanochromism and vapochromism simultaneously by applying cuprophilic interactions as a multi-responsive chromophore. The organic ligand 4-dpda is chosen to amplify the perturbation toward metallophilic interations for steric hindrance, and many of the molecular interactions of its multi-phenyl moieties are sensitive to tiny disturbances and will translate the effects to the Cu4I4 core of compound 1. Structural and spectrographic investigations show that the changes in luminescence result from the disturbed cuprophilic interactions.

An example of structural evolution from inclined polycatenation to parallel polyrotaxane-like interpenetration is demonstrated by modifying the (6,3) layer. Notably synergies of co-ligand binding mode and metal coordination geometry provide the appropriate constituent motifs necessary to instill this entanglement variation.