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Zwitterions and polyoxometalates (POMs) are two kinds of functional moieties with very different properties for applications in different fields. We have developed an effective strategy to successfully immobilize these two different moieties into the frameworks of porous hybrid materials, in which the POM units act as templates and photoactive moieties. These hybrid materials demonstrate remarkable efficiency for selective scavenging and photolysis of cationic dyes from polluted water, and up to 10% dye uptake and quantitative photolysis of dyes have been realized.

Glycan from green tea was extracted with boiling water. The extraction temperature, extraction time and ratio of liquid to solid were optimized by using response surface methodology (RSM). The maximum yield of tea glycan extracts (2.93%) was obtained when glycans in green tea were extracted. The optimal extraction conditions for the glycans from green teas were: extracting temperature 98 °C, extracting time 50 min and rate of liquid to solid 6:1. Tea glycan, with an average molecular weight of 8.3 × 10 5 Da, contained rhamnose (Rha), arabian (Ara), xylose (Xyl), mannose (Man), galactose (Gal), and glucose (Glc) in molar ratios of 1.06:2.31:5.17:0.91:3.06:4.24. Ethanol extract of tea showed significantly higher antitumor activity against the SKOV-3 cells than tea glycan. These results indicate that the higher antitumor activity of ethanol extracts from tea may be related to their polyphenol contents.

A new flexible bowl-shaped zwitterionic complex, 1,1′,1′′-(2,4,6-trimethylbenzene-1,3,5-triyl)tris(methylene)tris(4-carboxypyridinium) tribromide (H3LBr3) was designed and synthesized, which was subsequently used as an efficient ligand to construct four interesting coordination polymers of [Cu2Cl2L2(H2O)2]·Cl·Br·4H2O (1), [ZnLBr]·NO3·H2O (2), [Cd2L2Br2]·2NO3·4H2O (3), and [Cd2L2(Inic)(H2O)4(MeOH)2]·Br·2NO3·3H2O (Inic = isonicotinlate, 4) by reaction of L ligand with corresponding metal salts or in the presence of isonicotinic acid. In these coordination polymers, L ligands link up metal nodes to form distinct linear networks. Two bowl mouths of two L ligands surround each other to form a ball-shaped building synthon in compounds 1 and 4, while the linear networks in 2 and 3 are in cylinder-shaped configurations. The luminescent spectra of L and compounds 1, 2, 3, and 4 suggested that the potential field around L ligand should be an important factor on the fluorescent emissions. The successful construction...

A 1,8-naphthalenecarboxylic anhydride-4,5-dicarboxylate (L) bridged copper(II) dimeric molecular module [Cu2L2(DMF)2(H2O)2] (1) can self-organize into a solid-state supramolecular architecture. The combination of the multitopic contact sites of hydrogen bonds coupled with two bulky aromatic cores promoted the molecule to self-link into a solid-state supramolecular architecture, which was almost insoluble in water and common organic solvents. Solid 1 can heterogeneously catalyze the cross-coupling of arylboronic acids with imidazole in the absence of a base or additive to generate the corresponding coupling products in excellent yields in methanol at 50 °C, which can be recovered and recycled by a simple filtration and was used for six consecutive cycles with consistent activity.

The reaction of 1,4,5,8-naphthalene-tetracarboxylic dianhydride and NiCl2·6H2O in a mixed solvent of pyridine and water afforded green crystals of [Ni2L(Py)4(H2O)6]·Py·10H2O (L = 1,4,5,8-naphthalene-tetracarboxylate; Py = pyridine; 1), which consists of centrosymmetric related nickel(II) binuclear units, pyridine and lattice water molecules. The lattice water molecules hydrogen bond into a water tape network comprising of tetrameric water clusters and pentameric water clusters as subunits. The water tapes are further linked by hexameric water clusters to form a water sheet, which is further staked into a 3D supramolecular network comprising metal–organic residues as guests within the columned channels.

Four porous metalloporphyrinic framework materials, [(CH3)2NH2][Zn2(HCOO)2(Mn(III)-TCPP)]·5DMF·2H2O (1; H6TCPP = tetrakis(4-carboxyphenyl)porphyrin), [(CH3)2NH2][Cd2(HCOO)2(Mn(III)-TCPP)]·5DMF·3H2O (2), [Zn2(HCOO)(Fe(III)(H2O)-TCPP)]·3DMF·H2O (3), and [Cd3(H2O)6(μ2-O)(Fe(III)-HTCPP)2]·5DMF (4) were synthesized by heating a mixture of M(III)Cl-H4TCPP (M = Mn and Fe) and M' (M' = Zn or Cd) nitrate in a mixed solvent of DMF and acetic acid. Compounds 1-3 are built up from M'2(COO)4 paddle-wheel subunits bridged by M(III)-TCPP and formate ligands to form their 3D connections. The formate pillar heterogeneously connects with M and M' cations in 1 and 2 and homogeneously joins M' cations in 3. The μ2-O bridged Fe(III)-HTCPP dimer performs as a decadentate ligand to link 10 cadmium cations for the formation of an interesting 3D coordination network of 4. The four porphyrinic frameworks present interesting catalytic properties in the selective epoxidation of olefins, oxidation of cyclohexane, and intermolecular aldol reaction of aldehydes and ketones.

A new bifunctional aromatic azolium derivative is designed and synthesized, which is used to construct two MOF′s containing imidazolium moieties.

A new bifunctional N-heterocyclic carbene (NHC) precursor was used to construct two metal–organic frameworks, which can anchor palladium(II) sites by post-modification, presenting remarkable framework dependent catalytic activities.

The reaction of 5,10,15,20-tetra(carboxyphenyl)porphyrin (H6TCPP) or metalated M-H4TCPP (M = CoII, NiII, CuII and VIVO) with lead nitrate afforded five metal–organic frameworks (MOFs), [Pb2(H2TCPP)]·4DMF·H2O (1), Pb2(Co–TCPP)(H2O)(DMF)]·1.5DMF (2), [Pb2(Ni–TCPP)(DMF)(H2O)]·1.5DMF·2H2O (3), [Pb2(Cu–TCPP)(DMF)(H2O)]·1.5DMF·2H2O (4) and [Pb2(VO–TCPP)(H2O)2]·4DMF (5). Single crystal X-ray diffraction analysis revealed that the five MOFs based on the TCPP scaffolds differ in framework topologies and porphyrin configurations that are varied from flat to wavy to bowl-shaped. The porphyrin cores play a pivotal role in the formation of the distinct coordination frameworks by controlling the stacking fashion of the porphyrins, the coordination modes of TCPP and the coordination spheres of the Pb2+ cations. Solid-state photoluminescent experiments suggest that the emissions of these compounds are dependent on the framework structures, and are insensitive to the porphyrin cores.