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An I2-mediated aerobic cyclization reaction of anilines, alkynes, and tertiary amine has been reported. In this protocol, a novel strategy for the synthesis of quinolines using tertiary amines as a C1 synthon via C–N bond cleavage.

A nanoflower-like bimetallic FeP/CoP-1-350 heterostructure electrocatalyst with rich interfaces shows excellent OER electrocatalytic activity.

The construction of all-carbon molecule frameworks remains challenging. Herein, we report a facile and efficient one-pot synthesis of a novel all-carbon stair containing dimerized pentalene core using inexpensive cyclopropyl alkyne catalyzed by in situ generated Cu(I) from the comproportionation reaction of Cu(II) salt and Cu powder under mild reaction conditions. The reaction proceeds via sequential acetylenic coupling, followed by cyclization and [2 + 2] cycloaddition to directly produce pentalene dimer, which is difficult to access by other established methods. Different mechanistic paths were studied for the pentalene formation using density functional theory, suggesting that the reaction also proceeds through acetylenic coupling followed by cyclization and [2 + 2] cycloaddition. Based on the activation energy barriers, Path 1 has the rate-determining step of 38.63 kcal/mol, which is the most thermodynamically preferred one among the four paths.

Two novel coordination polymers {[Cu4(H2dam-dap)4(ClO4)2]·2ClO4}n (1) and [Cu3(H2dam-dap)2(N3)2(NO3)2]n (2) have been obtained through the copper salts and 3-(3-Amino-propylimino)-butan-2-one oxime (H3dam-dap) ligand, which was synthesized by one-pot reaction in the preparation process of complexes. Single-crystal X-Ray analysis shows that complex 1 displays a cage-like 12-MC-4 metallacrown structural unit with the sides exhibiting Cu–N–O repeat units, and the cage-like structures have been linked into one 1D chain by the bridges of ClO4− anions; 2 possesses trinuclear [Cu3(H2dam-dap)2]4+ unit with three Cu ion locating in a linear arrangement, and the adjacent trinuclear units are linked into a 2D coordination polymer by bridging nitrate anions. Magnetic studies reveal that 1 displays ferromagnetic coupling between metal centres, and 2 exhibits antiferromagnetic interaction and field-induced frequency-dependent behavior.

The resonance assisted hydrogen bond (RAHB) is a special type of hydrogen bonding (HB). With the influence of the π-electron delocalization, the RAHB is stronger than normal HB which is solely base...

The exploitation of efficient hydrogen evolution reaction (HER) electrocatalysts has become increasingly urgent and imperative; however, it is also challenging for high-performance sustainable clean energy applications. Herein, novel Co9S8 nanoparticles embedded in a porous N,S-dual doped carbon composite (abbr. Co9S8@NS-C-900) were fabricated by the pyrolysis of a single crystal Co-MOF assisted with thiourea. Due to the synergistic benefit of combining Co9S8 nanoparticles with N,S-dual doped carbon, the composite showed efficient HER electrocatalytic activities and long-term durability in an alkaline solution. It shows a small overpotential of −86.4 mV at a current density of 10.0 mA cm−2, a small Tafel slope of 81.1 mV dec−1, and a large exchange current density (J0) of 0.40 mA cm−2, which are comparable to those of Pt/C. More importantly, due to the protection of Co9S8 nanoparticles by the N,S-dual doped carbon shell, the Co9S8@NS-C-900 catalyst displays excellent long-term durability. There is almost no decay in HER activities after 1000 potential cycles or it retains 99.5% of the initial current after 48 h.

Naphthalimide has emerged as an interesting DNA intercalator and possessed attracting antitumor properties. In this context, naphthalimide group was linked to platinum(IV) core to construct a series of new mono naphthalimide platinum(IV) derivatives. The title compounds exert effective antitumor activities to the tested tumor cells lines in vitro, especially the one with propionyl chain displays comparable or even better bioactivities than platinum(II) reference drugs cisplatin and oxaliplatin. Moreover, the mono naphthalimide platinum(IV) derivative displays comparable tumor growth inhibitory competence against CT26 xenograft tumors in BALB/c mice in vivo without severe toxic effects in contrast to oxaliplatin. A dual DNA damage mechanism was proven for the title complex. Both naphthalimide ligand and the liberated platinum(II) moiety could generate DNA lesions to tumor cells synergistically and active the apoptotic pathway by up-regulating the expression of caspase 9 and caspase 3. Meanwhile, the conversion of platinum(II) drug into tetravalent form by incorporating naphthalimide moiety increases the uptake of platinum in whole cells and DNA remarkably. All these facts might be the factors for the title platinum(IV) complexes to overcome platinum(II) drug resistance. Additionally, the mono naphthalimide platinum(IV) complex could interact with human serum albumin by hydrogen bond and van der Waals force which would further influence their storage, transport and bioactivities.

Two heterometallic metallacrown complexes, [Er{Cu4(butyrat)4}2]·Cl3·MeOH·26H2O (1) and [Yb{Cu4(butyrat)4}2]·Cl3·MeOH·26H2O (2) (H2butyrat = 3-aminobutyric hydroxamic acid), have been reported. X-ray crystallographic analysis reveals that the two complexes displayed nested-sandwich configurations with two 12-MC-4 metallacrown units capping LnIII in the centre. Magnetic studies revealed that 1–2 undergo antiferromagnetic coupling interaction. Magnetic measurements show that complex 2 displays frequency-dependent signals at a dc field of 1000 Oe, indicating field-induced single-molecule magnet behavior.

Heterometallic cluster-organic frameworks with fascinating architectures and multi-functionality have the potential to be applied in various fields. However, in comparison with p–d, d–d, and d–f heterometallic cluster-organic frameworks, p–f heterometallic cluster-organic frameworks are far less explored even though they possess multiple merits. Herein, two novel isomorphic 4p–4f heterometallic cluster-organic frameworks based on high-nuclear [Ln11Ge12] (Ln = Pr, L1 and Nd, L2) second building units have been successfully synthesized via a hydrothermal approach by using bis(carboxyethylgermanium) sesquioxide (H2E2Ge2O3, E = –CH2CH2COO–). The [Ln11Ge12] cluster is constructed with two Ln-capped Ge6-rings sandwiching a gear-like [Ln9] unit. The as-prepared 4p–4f heterometallic [Ln11Ge12] cluster-organic frameworks possess two-dimensional (2D) layered structures. Moreover, the property study reveals the selective and sensitive luminescence sensing of Fe3+ with L1, exhibiting its promising application in environmental monitoring.

Six novel heterobimetallic cyanide-bridged complexes formulated as {[Cu(dmpn)2]2[Fe(bpb)(CN)2]}[Fe(bpb)(CN)2](ClO4)2·2H2O (1), [Cu(dmpn)2][Fe(bbp)(CN)3]n·0.5nDMF·2.5nH2O (2), {[Cu(dmpn)2]1.5[Cr(CN)5(NO)]}n·3nH2O (3), {[Cu(dmpn)2]2[Fe(CN)6]}n·10nH2O (4), {[Cu(dmpn)2]4[Mo(CN)8]2}·CH3CN·2H2O (5), and {[Cu(dmpn)2]4[W(CN)8]2}·CH3CN·2H2O (6) (bpb = 1,2-bis(pyridine-2-carboxamido)benzenate, bbp = 2,6-bis(benzimidazoi-2-yl)pyridine, dmpn = 2,2-dimethyl-1,3-diaminopropane, DMF = N,N-dimethylformamide) were synthesized with one amine copper compound as an assembly segment and six polycyanometallates containing two, three, five, six or eight cyanide groups as building blocks. All of the six complexes have been characterized using elemental analysis, IR spectra, and powder and single crystal X-ray diffraction. Structural analysis revealed diverse structural types of complexes 1–6, ranging from discrete polynuclear entities (1) to a 1D single chain (2) to 2D (3, 5 and 6) and 3D (4) networks, clearly indicating the important role of the building block in tuning the structures of the target complexes. The magnetic properties of the reported cyanide-bridged complexes have been experimentally studied and theoretically simulated, disclosing ferro- or antiferromagnetic coupling between the low spin Fe(III) ion and Cu(II) ion and the antiferromagnetic interaction between the Cr(I) ion and the Cu(II) ion through the cyanide bridge. Furthermore, the nature of the magnetic coupling has been analysed based on the magneto-structural correlation.

Assembled from a reduced Schiff base tricarboxylate ligand H3L, two novel Cd-MOFs with the formulae {[Cd(HL)(bpy)]·1.25H2O·1.5DMF}n (LCU-107) and {[Cd(HL)(bpea)·H2O]·H2O·DMF}n (LCU-108) (where LCU stands for Liaocheng University, H3L = 5-(4-carboxybenzylamino)isophthalic acid, bpy = 4,4′-bipyridine, and bpea = 1,2-di(4-pyridyl)ethane), were obtained. LCU-107 possesses a 3D pcu framework based on dinuclear units. LCU-108 demonstrates an interesting 2D → 2D interdigitating and penetrating structure. The flexible carboxylate ligands can all bend in these complexes due to the rotation of –CH2–NH– groups. Luminescence measurements indicated that these two Cd-MOFs show highly selective and sensitive sensing activities toward acetylacetone (acac) and Cr2O72− through a luminescence enhancement and a quenching effect, respectively. The detection limits toward acac are as low as 0.136 and 0.058 ppm, respectively. To our knowledge, these two Cd-MOFs may represent very rare examples of special turn-on acac sensors, as well as being dual-responsive chemosensors for both acac and Cr2O72−.

We have prepared three 3d–4f heterometallic complexes, namely[Ln3Zn3(Hvanox)3(vanox)3(NO3)6(H2O)5]·nEtOH (LnIII = Dy, n = 3 (1), LnIII = Tb, n = 5 (2), LnIII = Er, n = 5 (3)), by the reaction of o-vanillin oxime (H2L) with Zn(NO3)2·6H2O and Ln(NO3)2·6H2O salts in the presence of triethylamine. Single Crystal X-ray diffraction shows Zn ions and Ln ions are linked together to display a windmill-like framework with the dinuclear LnZn(HL)(L) as flabellum. Magnetic measurements reveal that complexes 1 and 2 exhibit field-induced frequency-dependence signals, indicating single-molecule magnetism (SMM) behaviors, while complex 3 exhibits slow magnetic relaxation.

With the careful modulation of the relative ratio of Y3+/Eu3+and Y3+/Tb3+, two series of bimetallic RE-CPs (EuxY1−x and TbxY1−x) were successfully obtained through the isomorphous substitution method. Interestingly, the introduction of Y3+ ions does not change the fluorescence characteristic peak of 1-Eu and 1-Tb, but enhances its fluorescence lifetime and quantum yield. Experimental and theoretical simulation results show the co-doping process changes the intramolecular energy transfer process and reduces the non-radiative transition resulting from concentration quenching. Eu0.1Y0.9 and Tb0.1Y0.9 with the largest luminescence lifetime were selected as the representative research objects, their potential application for the detection of toxic metal ions and organic molecules was further investigated. Interestingly, Eu0.1Y0.9 and Tb0.1Y0.9 demonstrate high sensitivity and good selectivity towards Fe3+, Cr3+ and acetone. Besides, fine fluorescence visibility provides the necessary conditions for the preparation of simple and fast response fluorescent test papers in order to achieve real-time and convenient detection of these toxic materials.

Hydrogen generation from photocatalytic water-splitting is a promising approach of renewable energy storage and has the potential to ease energy shortage. During the past few decades, various materials have been developed as photocatalysts. But most especial single photocatalytic systems still suffer from low efficiency and poor stability. Constructing heterostructures is considered as a good strategy to address those issues, but some drawbacks of safety hazard, time-consuming and energy-intensive still restrict its further application. In this manuscript, we successfully synthesized Ni2P/CdS nanohybrids by using a green and facile method. The as-synthesized Ni2P/CdS with Ni2P grown in-situ on CdS can remarkably inhibit electron–hole recombination, and thus renders more generated electrons involving in the reaction of H+ reduced into H2. As a result, the optimized Ni2P/CdS heterostructure exhibits high photocatalytic performance with H2 evolution rate of 44.65 mmol g−1 h−1, far exceeding that of pristine CdS by a factor of 127. This green synthesized strategy will inspire the fabrication of other photocatalytic systems and may low-cost, high efficient, and eco-friendly photocatalysts be obtained.

Two 1-D lanthanide-based CPs (coordination polymers), Eu-CP and Tb-CP, have been solventhermally synthesized from a phenolic-linked tricarboxylate ligand 1,3,5-tri(2-carboxyphenoxy)benzene (H3L). Both complexes demonstrate stability and strong characteristic luminescence emissions in organic and water media. They also possess excellent luminescence sensing activities toward Fe3+ and Cr2O72−/CrO42− in DMF and aqueous solutions as well as simulated biological system. Notably, Tb-CP is one of the very few examples to effectively distinguish between CrO42− and Cr2O72− in aqueous and HEPES media. Both CPs could be simply and quickly regenerated at least five circles. The research on sensing mechanism indicated that the luminescence quenching may be related with the energy competition and weak interactions between CPs and sensing analytes.

Exploration of low-cost and earth-abundant photocatalysts for efficient photocatalytic H2 evolution from water is an attractive solution to the global energy and environmental problems. Although MoS2 has been proved as an efficient co-catalyst for the H2 evolution reaction (HER), controllably and accurately constructing MoS2-hybridized photocatalysts at where the electrons extracted still remains a challenge. Here, a facile two-step approach of photoetching-photodeposition has been developed to prepare MoSx/etched-CdS (Mo-Cd(e)-S) with heterostructure accurately constructed on the CdS surface defects. This structure can significantly accelerate photo-induced charge separation and transportation owing to the place of heterostructure construction matching well with that of electrons extracted, numerous active sites introduced, and shorter charge transfer path from bulk to surface. Therefore the charge recombination is significantly retarded. As a result, the Mo-Cd(e)-S exhibits outstanding photocatalytic performance with a state-of-the-art H2 generation rate of 22.5 mmol g−1 h−1 under visible light irradiation (λ ≥ 420 nm) which is 70 times higher than that of pristine CdS. This work opens a new avenue for the low-cost but high efficient photocatalysts development.

Two Cd(II) coordination polymers (CPs) were assembled from the mixed ligand strategy of π-conjugated aromatic polycarboxylates and bis(imidazole) linkers, with the structures being a 2-fold interpenetrating 3D bbf net for 1 and a 2D hxl sheet for 2. The fluorescence measurements revealed that both Cd(II) CPs were promising luminescent sensors for the detection of nitrofuran/nitroimidazole antibiotics (ABXs) with low detection limits. Besides, the luminescence quenching of the two Cd(II) CPs toward ABXs was investigated by using DFT calculations and spectral overlap experiments.

For catalytic system consists of Pd as active component and CeO2-ZrO2/Al2O3 (CZ/A) as support, the dispersion and oxidation state of Pd species, which are crucial to the catalytic performance, are closely related to the metal-support interaction. In this work, Pd species were introduced into CZ/A system at different thermal treating stages of the support, which brought about different Pd–CZ interaction. The characterization results reveal that when CZ/A support was thermal treated at 300 °C prior to the introduction of Pd species, a special Pd/CZ/A catalyst with Pd species semi-embedded in CZ/A was acquired, which exhibits excellent thermal stability owing to the appropriate Pd–CZ interaction. During thermal aging process, encapsulation and aggregation of Pd species are effectively inhibited for Pd/CZ/A with semi-embedded structure. Thus, higher dispersion, more oxidative Pd2+ species and larger amount of oxygen vacancies are maintained after aging, which consequently lead to its superior three-way catalytic performance.

The enthalpies of dilution of protocatechualdehyde and p-hydroxybenzaldehyde in the aqueous sodium chloride solutions were measured by using a mixing-flow microcalorimeter at 298.15 K. Densities of the ternary homogeneous systems at different temperatures (293.15, 298.15, 303.15, 308.15, and 313.15 K) were also measured with a quartz vibrating-tube densimeter. The homogeneous enthalpic interaction coefficients (h2, h3, and h4) were calculated according to the excess enthalpy concept based on the calorimetric data. The apparent molar volumes (Vϕ) and standard partial molar volumes (Vϕ0) of the investigated system were computed from their density data. The variation trends in h2 and Vϕ0 with increasing salt molality were obtained and discussed in terms of the (solute + solute) and (solute + solvent) interactions. The experimental results showed that the molecular structures of protocatechualdehyde and p-hydroxybenzaldehyde, especially the number of hydroxyl groups, have evident influence on their thermodyna...

Mild crosslinking methods, which have a strong influence on biomedical hydrogels and scaffolds, have attracted wide attention in recent years. In this project, native chemical ligation (NCL) was utilized to prepare biocompatible and biodegradable hydrogels using naturally derived poly(glutamic acid) (PGA) with no additives or by-products. Firstly, thiolactone-grafted poly(glutamic acid) (PGA-HC) and cysteine-grafted poly(glutamic acid) (PGA-C) precursors were synthesized. Their structure was confirmed by nuclear magnetic resonance (NMR). Then, hydrogels crosslinked by NCL were formed by blending buffered solutions of PGA-HC and PGA-C with no additives under physiological conditions. After that, the equilibrium water content, morphology, degradation rate and mechanical properties of the hydrogels were characterized in detail. The data showed that the PGA hydrogels had gelation times, water contents and mechanical properties that were tunable by adjusting the precursor composition. Furthermore, the biocompatibility of the hydrogels was confirmed by an MTT assay. These characteristics provide a potential opportunity for the NCL hydrogels as wound dressings, skin fillings, drug delivery vehicles and tissue regeneration matrices.

Four cyanide-bridged FeIII&ndash, MnIII complexes {[Fe(qxcq)(CN)3][Mn(L1)(H2O)]}[Mn(L1)(H2O)(CH3OH)](ClO4)&middot, 1.5MeOH&middot, 0.5H2O (L1 = N,N&prime, bis(3-methoxy-5-bromosalicylideneiminate) (2), {[Fe(qxcq)(CN)3][Mn(L2)]}2&middot, 0.5H2O (L2 = N,N&prime, ethylene-bis(3-ethoxysalicylideneiminate)) (3), [Fe(qxcq)(CN)3][Mn(L3)] (L3 = bis(acetylacetonato)ethylenediimine) (4), [Fe(qxcq)(CN)3][Mn(L4)]&middot, 0.5CH3CN&middot, 0.25H2O (L4 = N,N&prime, (1,1,2,2-tetramethylethylene)bis(salicylideneiminate)) (5), were prepared by assembling a new structurally characterized mer-tricyanoiron(III) molecular precursor (Ph4P)[Fe(qxcq)(CN)3]&middot, 0.5H2O (qxcq&minus, = 8-(2-quinoxaline-2-carboxamido)quinoline anion) (1) and the corresponding manganese(III) Schiff base compound. Complexes 2and 3containa cyanide-bridged heterobimetallic dinuclear entity, which can be further dimerized by self-complementary H-bond interactions through the coordinated water molecule from one complex and the free O4unit from the adjacent complex. Complexes 4 and 5 area one-dimensional coordination polymer (CP) comprised of the repeated [Mn(Schiffbase)-Fe(qxcq)(CN)3] units. Complex 4 shows a linear-chain conformation with two trans-located cyano groups bridgingthe neighboring Mn units, while complex 5 is a zigzag-like 1D CP, where the two cyano groups in cis configurationfunction as bridges. In bothcomplexes 4 and 5, the inter-chain &pi, &ndash, &pi, stack interactions within the aromaticrings of cyanide precursor extend the 1D chain into the supermolecular 2D networks. The magnetic property has been experimentally studied and theoretically fitted over the four Fe(III)-Mn(III) complexes, revealing the antiferromagnetic interaction in complexes 2 and 4 and the unusual ferromagnetic coupling in complexes 3 and 5 between the Fe(III) ion and the Mn(III) ion bridged by the cyano group. Furthermore, the different magnetic coupling nature has been analyzed on the basis of the magneto-structure correlation of the mer-tricyanometallate-based Fe(III)-Mn(III) magnetic system.

Two isostructural (3,6)-connected porous coordination polymers topologically featuring both self- and interpenetration have been successfully synthesized. The porous material shows a reversible crystalline-to-amorphous transition associated with the removal and recapture of guest molecules. Particularly, the porous material demonstrates selective detection of nitrobenzene through fluorescence quenching.

Six metallacrown complexes {La(OAc)(H2O)2[15-MCCu(N)glyha-5](H2O)4}·2NO3·5H2O (1), {Gd(OAc)(H2O)[15-MCCu(N)glyha-5](H2O)3}·2NO3·5H2O (2), {Tb(OAc)(H2O)[15-MCCu(N)glyha-5](H2O)4}·2NO3·4H2O (3), {Pr(NO3)(H2O)2[15-MCCu(N)glyha-5](H2O)}·2NO3·8H2O (4), {Nd(NO3)(H2O)2[15-MCCu(N)glyha-5](H2O)2}·2NO3·7H2O (5) and {Sm(NO3)(H2O)2[15-MCCu(N)glyha-5](H2O)2}·2NO3·6H2O (6) (glyha2− = dianion glycinehydroxamic acid) have been synthesized and structurally characterized by X-ray single crystal diffraction, IR spectroscopy and elemental analysis. Spectroscopic studies show that these complexes bind to CT-DNA via an intercalative mode and cause a more B-like to a more C-like conformational change. Magnetic measurements indicate that complexes 1, 3, 4, 5 and 6 dominantly show antiferromagnetic interactions between metal centers, whereas complex 2 reveals ferromagnetic interactions.

Protocatechuic acid (PA) is a natural phenolic compound which has been proven to have chemopreventive property against chemically induced carcinogenesis. The mixing enthalpies of PA with N-glycylglycine in sodium phosphate and potassium phosphate buffer solutions with different pH values have been investigated by mixing-flow isothermal microcalorimetry at T = 298.15 K. The heterotactic enthalpic interaction coefficients (hxy) in the pH range of phosphate buffer solution from 3.0 to 8.0 have been calculated according to the McMillan–Mayer theory. Trends of the enthalpic pairwise interaction coefficients (hxy) with increasing pH in both phosphate buffer solutions were obtained. The solvent and pH dependence of the hxy were discussed in terms of molecular interactions between solvated solute molecules.

The double chloride-bridged dimer of a dinuclear dysprosium(III) single-molecule magnet (SMM) was successfully isolated by assembling centrosymmetric dinuclear Dy2 SMMs. Such structural transformation involves the generation and cleavage of chloride bridges and leads to consecutive transformations of one- and two-step slow relaxation of magnetization.

Mixed 3d-4f 12-azametallacrown-4 complexes, [Mn2 Ln2 (OH)2 (hppt)4 (OAc)2 (DMF)2 ]⋅2 DMF⋅H2 O [Ln=Dy (1), Er (2), Yb (3), Tb (4) and Y (5), H2 hppt=3-(2-hydroxyphenyl)-5-(pyrazin-2-yl)-1,2,4-triazole)], were synthesized by reactions of H2 hppt with Mn(OAc)2 ⋅4 H2 O and Ln(NO3 )3 ⋅6 H2 O. This is the first 3d-4f azametallacrown family to incorporate Ln ions into the ring sets. These isostructural complexes exhibit alternating arrangements of two Mn and two Ln ions in the rings with each pair of metal centers bound by an NN group and μ2 -O bridging. Magnetic measurements revealed dominant antiferromagnetic interactions between metal centers, and frequency-dependent out-of-phase (${\chi {^\prime}{^\prime}_{\rm{M}} }$) signals below 4 K suggest slow relaxation of magnetization.

Five organotin(IV) compounds Ph3SnL (1), (R2Sn)4O2L4 [R = n-Bu (2), n-Oct (3)], (R2Sn)4O2L2Cl2 [R = n-Bu (4), Me (5)], have been synthesized from the reactions of 2-phenyl-4-selenazole carboxylic acid (HL) with the corresponding organotin(IV) oxide or chlorides. These compounds have been characterized by elemental analysis, IR, 1H, 13C and 119Sn NMR spectroscopy, and single crystal X-ray diffraction analysis. Structural studies reveal that compound 1 exhibits a mononuclear four-coordinated tetrahedral geometry. Differently, the crystal structures of compounds 2–5 reveal the formation of the tetranuclear species containing a planar Sn4O4 core. All compounds were screened for their in vitro cytotoxic activities toward three cancer cell lines (Caco-2, A549, and HCT-116) and one normal rat hepatocyte cell line (BRL). The results indicate that both di-n-butyltin(IV) and triphenyltin(IV) derivatives not only show excellent cytotoxic activities on cisplatin-sensitive lung cancer cell line A549 and but also exhibit good cytotoxicity against cisplatin-insensitive colon cancer cell lines HCT-116 and Caco-2. Whereas, dimethyltin(IV) and di-n-octyltin(IV) complexes exhibit lower or no cytotoxic activity. The structure–activity relationship of the cytotoxicity of the title complexes has also been discussed.

A Cd(II)-based metal–organic framework, {[Cd2L(H2O)2]·DMF·H2O}n (1), has been successfully constructed from a new flexible antler-like multidentate ditopic ligand (H4L). This metal–organic framework shows highly sensitive fluorescence sensing of nitrobenzene.

Three new ZnII–ditetrazolate coordination polymers (CPs), namely [Zn(m-pdtz)(4,4′-bipy)(H2O)]n (1), [Zn2Cl2(m-pdtz)(4,4′-bipy)]n (2) and [Zn2(OH)2(m-pdtz)]n (3) (4,4′-bipy = 4,4′-bipyridine, m-H2pdtz = 5,5′-1,3-phenylene-ditetrazole), have been constructed by an in situ ditetrazolate-ligand synthesis system. The formation of m-pdtz2- ligand involves the Sharpless [2 + 3] cycloaddition reaction between isophthalonitrile (IPN) and NaN3 in the presence of Zn2+ ions as Lewis-acid catalysts under hydro/solvothermal conditions. Single-crystal structural analyses reveal that compound 1 exhibits a new 6-connected 3D structural topology constructed from dimeric {Zn2} clusters as secondary building units (SBUs), compound 2 represents a 2D sql structural feature built from rhombic tetrameric {Zn4} rings as SBUs, while compound 3 displays a new (4,6)-connected 3D structural topology constructed from rod-shaped 1D Zn-chains as SBUs. Regarding these three CPs, we have performed a thorough investigation on their crystal structure, topology, and fluorescence property.

Crystallization and decomposition of organolead trihalide perovskites (OTPs) are very sensitive to the presence of water in precursor or in ambient conditions. Thus, understanding equilibrium behaviours (crystallization and decomposition) of OTPs in aqueous solution is very critical for OTP solar cells fabricated with water-based precursor solutions. Here, equilibrium behaviours in an aqueous solution of CH3NH3PbI3 (MAPbI3) single crystals (MSCs) were studied. Diethyl ether, as an antisolvent, effectively diffused and induced MSC growth by screening different solvents (diethyl ether, tetrahydrofuran, dichloromethane, and chloroform). The structure transforms from the initial PbI2 to intermediate (HxPbI2+x·xH2O) and finally MSCs were observed by X-ray diffraction. Decomposition of MSCs in aqueous solution was significantly enhanced by potassium iodide coordination and inhibited by CH3NH3I (MAI) addition. We ascribed this inhibition behaviour to suppressing MAI migration from the MSC crystal structure. Finally, the optical properties of MSC were studied.

Two Fe-based porous MOFs have been constructed from dimeric Fe-clusters and rod-shaped heterobimetallic Fe/Na-chains as SBUs, respectively. Notably, both of them exhibit highly selective CO2 uptake over CH4 and N2 owing to abundant multiple active sites.

Eight mixed-ligand coordination compounds, [Zn(PA)(bpp)]n (1), {[Cd(PA)2(Hbpp)2(H2O)2]·2H2O}n (2), [Zn(PA)(bbi)]n (3), [Cd(PA)(bbi)(H2O)]n (4), {[Cd3(PA)2(bbi)3(Cl)2]}n (5), {[Zn6(PA)5(datrz)2(Hdatrz)2(H2O)2]·16DMF}n (6), [Cd2(PA)(datrz)2(DMF)2]n (7), and {[Cd2(PA)2(bix)2(DMF)2]·4DMF}n (8) (bpp = 1,3-bi(4-pyridyl)propane, bbi = 1,4-bis(imidazol-1-yl)butane, H2datrz = 3,5-diamino-1,2,4-triazole, bix = 1,4-bis(imidazol-1-ylmethyl)benzene), have been synthesized through the reaction of zinc and cadmium salts with pamoic acid (H2PA) and different N-donor ligands. The assembly of the ligands in different coordination modes and conformations leads to fascinating structures. 1 and 3 afford an interpenetrating polythreaded 2D → 3D motif composed of 44 sql undulated sheets, while right- and left-helices are alternatively arranged in 3. 2 possesses an interesting 3-D supramolecular network with 1-D hydrogen-bonded chains spanning different directions. 4 and 5 display both polyrotaxane and polycatenane characteristics. In 4, two 2,4-connected (4·85) nets interlocked with each other, forming a 2D → 2D polycatenating network. 5 exhibits a twofold interpenetrated (3,5,6)-connected (3·5·6)(3·52·67)(32·54·66·72·9) topology. 6 and 7 represent rare pentanodal (3,4)-connected and binodal (3,4)-connected frameworks with topologies of (4·5·6)(4·8·10)(52·6·8·9·11)(4·5·6·8·92)(4·5·7) and (4·6·8)(4·62·83), respectively. 8 displays 3-fold interpenetrated 4-connected SrAl2 topology with flexible bix ligands bridging Cd centers to form right- and left-helices. The mixed-ligand effect of the conformations of the PA ligand and N-heterocyclic coligands as well as the metal centers on the assembly of frameworks is unravelled in detail. Solid-state luminescence properties of all compounds were reported as well. Moreover, fluorescence properties of compounds 6 and 8 in various solvent suspensions at room temperature have also been investigated.

Photocatalytic H2 evolution from water splitting offers an attractive scientific and technological method to address the energy and environmental crisis. In this study, noble-metal-free Zn0.5Cd0.5S@MoS2 core@shell nanoheterostructures were elaborately designed and successfully synthesized. The visible-light-driven photocatalytic performance investigation shows that the Zn0.5Cd0.5S@MoS2 exhibits a state-of-the-art H2 evolution rate of 40.2 mmol g−1 h−1 far exceeding that of pristine Zn0.5Cd0.5S by more than 57 times. Moreover, thanks to the protection of MoS2 shells, the Zn0.5Cd0.5S@MoS2 can retain long-term stability in four-cycles of 24 h reactions. Furthermore, a tentative mechanism on H2 generation was systematically investigated and proposed, which contributes to understand the enhanced photocatalytic activity of the Zn0.5Cd0.5S@MoS2 heterostructures and may inspire the synthesis of other desirable catalytic systems.

Hydrothermal reactions of aromatic 3,3′,5,5′-biphenyltetracarboxylic acid (H4bpt) and the transitional metal cations in the presence of rigid or flexible N-donor ancillary ligands afford nine novel coordination polymers, namely, [M(H2bpt)(Hpptp)]n (M = Mn (1), Fe (2), Co (3), and Zn (4)), [Mn2(bpt)(Hpptp)2]n (5), {[Zn3(Hbpt)(bpt)(H2O)2][(4,4′-H2bmib)0.5]·H2O}n (6), {[Cu(bpt)0.5(4,4′-bimbp)]·H2O}n (7), {[Co(H2bpt)(2,7-dfo)]·H2O}n (8), and {[Ni2(bpt)(4,4′-bibp)2.5(H2O)]·3(H2O)}n (9) (Hpptp = 2-(3-(4-(pyridin-4-yl)phenyl)-1H-1,2,4-triazol-5-yl)pyridine; 4,4′-bmib = 4,4′-bis(2-methylimidazol-1-yl)benzene; 4,4′-bimbp = 4,4′-bis(imidazol-1-ylmethyl)biphenyl; 2,7-dfo = 2,7-di(imidazo-1-ly)-9H-fluoren-9-one; 4,4′-bibp = 4,4′-bis(imidazol)biphenyl). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Complexes 1–4 are isomorphism and feature a similar 2-fold interpenetrating 2D heli...

Two genuine supramolecular isomers of Cd(II) coordination polymers with an identical formula of [Cd(pptp)(ox)]n (1a and 1b) (pptp = 2-(3-(4-(pyridin-4-yl)phenyl)-1H-1,2,4-triazol-5-yl)pyridine, H2ox = oxalic acid) have been hydrothermally synthesized and characterized. Both compounds possess the rod-like binuclear [Cd2(pptp)2] subunit, which are linked by the ox ligand to afford either a flat or wavy two-dimensional (2D) 63-hcb network, depending upon whether the additive agent is used for the reaction. The photoluminescence behaviour of the compounds was also discussed.

Two new mesoporous magnesium silicate gel adsorbents, MgO x 2SiO2 and MgO x 6SiO2, have been successfully prepared by hydrothermal method. The synthetic factors including reaction pH, temperature, time and calcination temperature were studied. The aiming products were characterized by N2 adsorption/desorption isotherms, FT-IR spectroscopy and Scanning Electron Microscopy (SEM). The adsorption behaviors for cobalt ions were also systematically investigated. The results show that the reaction pH was the decisive factor for Si/Mg mole ratios. The special surface areas are 534.29 m2 x g(-1) for MgO x 2SiO2 and 181.61 m2 x g(-1) for MgO x 6SiO2, respectively. The maximum adsorption capacities of MgO x 2SiO2 and MgO x 6SiO2 for cobalt ions are 135.5 and 52.5 mg x g(-1). Furthermore, the experimental data are well described by pseudo-second order adsorption and Langmuir isotherm models. The experiment would afford one excellent adsorbent for solving the wastewater pollution and also providing metal cobalt for modern industry including new energy car.

Two heterothiometallic clusters modified by 1,1′-bis(diphenylphosphino) ferrocene (dppf) ligand [(Ag4Mo2S8)(dppf)2] (1) and [(Ag4Mo2S6O2)(dppf)2] (2) have been synthesized and characterized. X-ray single-crystal studies reveal that the structures of the two clusters are both hexagonal prism-shaped cages, which are modified by dppf ligands in rarely quasi-closed mode. While, the terminal atoms of the hexagonal prism cages are different, S atoms for 1 and O atoms for 2. The discrete clusters of 1 and 2 are connected to form 2-D supramolecular layers through hydrogen bonds C–H···S, C–H···π for 1 and C–H···O for 2. The different supramolecular interactions may be caused by the different terminal atoms, which also result in different fluorescence emissions and oxidation potentials.

Crystallization of a Schiff base with nickel acetate in different solvents yields a tetranuclear (dicubane-like [Ni4O4] core with two missing vertices) and a hexanuclear cluster ([Ni6O6] core with two nickel(II) ions attached to a [Ni4O4] cubane through oxygen bridges). Metal centers within these clusters exhibit ferromagnetic and antiferromagnetic coupling interactions, respectively.

Five novel compounds, {[Ni(PA)(bpe)(H2O)2]·DMF}n (1), {[Zn(PA)(bpe)]·DMF}n (2), {[Zn(PA)(bpe)]·2DMF·CH3OH}n (3), {[Cd2(PA)2(bpe)2(H2O)]·3.5H2O}n (4), {[Ni2(PA)2(bpp)2(H2O)3]·2DMF}n (5), based on pamoic acid (H2PA) (bpe = 1,2-bi(4-pyridyl)ethane, bpp = 1,3-bi(4-pyridyl)propane) have been synthesized. In such a system, both the PA2– anion ligand and dipyridyl ligands act as bipodal linkers, connecting the metal centers in square or tetrahedral geometries into 4-connected topologies with different entangled modes: 3-fold interpenetrating CdSO4 net (65.8) (1), roto-translational [2 + 2] interpenetrating diamond pseudosupramolecular isomers (2 and 3), 3-fold interpenetrating (6.74.8)(64.7.8) (4) and (6.85)(64.82) net with both 2-fold interpenetrating and self-penetrating characters (5), respectively. The formation of unique penetrating frameworks was investigated in detail. Gas adsorption and photoluminescent properties of the compounds have also been explored.

Two new carborane complexes containing closo- or nido-carborane diphosphine ligands with the formula: complex (1) and (2) have been synthesized and characterized by elemental analysis, 1H and 13C NMR spectroscopy and X-ray structure determination. The X-ray structure analyses revealed that the carborane diphosphine ligand was degraded from closo-1,2- to nido-[ in complex 1, while the closo nature of the starting ligand was retained in complex 2. In either of the two complexes, the carborane diphosphine ligand was coordinated bidentately to the Hg(II) or Ag(I) center through its two phosphorus atoms, therefore forming a five-member cheating ring between the carborane ligand and the metal center. The coordination geometry of the metal atom is distorted tetrahedron formed by unit in complex 1 and unit in complex 2, respectively.

Solvothermal synthesis method has been successfully introduced into the diphosphine carborane system, and two new nickel complexes containing nido-carborane diphosphine ligand [7,8-(PPh2)2-7,8-C2B9H10]− with the formula [Ni2(μ-Cl)(μ-OOPPh2){7,8-(PPh2)2-7,8-C2B9H10}2]·CH2Cl2 (1) and [H3O][NiBr2] {7,8-(PPh2)2-7,8-C2B9H10}·C6H6 (2) were obtained by the reactions of 1,2-(PPh2)2-1,2-C2B10H10 with NiCl2·6H2O or NiBr2·6H2O in CH2Cl2 under the solvothermal condition. Both of the two complexes have been characterized by the elemental analysis, FT-IR, 1H and 13C NMR spectroscopy and single crystal X-ray diffraction. The X-ray structure analysis for these two complexes reveals the nido-nature of the carborane diphosphine ligand, indicating that the solvothermal synthesis is an efficient method for the degradation of the closo-carborane diphosphine ligand.

Five coordination polymers with four different typological structures have been obtained based on 2,3,5,6-tetramethyl-1,4-benzenedicarboxylate acid (H2TBDC) and bipyridine ligands: 1D zigzag chain Cd(2,2′-bpy)(TBDC)(H2O)·H2O (1), 2D grid with (4,4)-net Co(H2O)2(4,4′-bpy)(TBDC)·2H2O (2), 3D interpenetrating frameworks with diamond topology Ni(4,4′-bpy)(TBDC) (3) and Cu(4,4′-bpy)(TBDC) (4), 3D porous framework with pcu network Co2(4,4′-bpy)(TBDC)2·2H2O·5DMF (5). Especially, complexes 2 and 5 with different topologies were obtained by use of the same reactant but change of the solvents. The gas sorption of complex 5 has also been studied.

The novel dimeric manganese-substituted polyoxotungstate Na10[(α-B-ZnW9O34)2W2Mn2(H2O)2](OH)2·34H2O (1) has been designed and synthesized from the hydrothermal reaction of Na2WO4·2H2O, MnCl2·4H2O, and ZnCl2 in a Teflon-lined stainless steel autoclave at 140°. X-ray diffraction analysis results reveal that compound (1) crystallizes in the monoclinic system, space group P2(1)/n, with a = 13.0901(3) A, b = 17.8242(4) A, c = 21.2401(5) A, β = 93.6380(10)°, Z = 1, V = 4945.8(2) A3, F(000) = 5244, Dc = 3.974 g/cm−3, μ(Mo-Kα) = 2.4037 cm−1, λ(Mo-Kα) = 0.71073 A. The structure was refined to R = 0.0631 and wR = 0.1532. The polyoxoanion of [(α-B-ZnW9O34)2W2Mn2(H2O)2]8− consist of two Keggin lacunary α-B-ZnW9O34 12− moieties linked via a rhomblike W2Mn2O16 group leading to a sandwich-type structure. The new dimeric polyoxotungstate Na10[(α-B-ZnW9O34)2W2Mn2(H2O)2](OH)2·34H2O (1) has been designed and synthesized from the hydrothermal reaction of Na2WO4·2H2O, MnCl2·4H2O, and ZnCl2 in a Teflon-lined stainless steel autoclave at 140°. X-ray diffraction analysis results reveal that the polyoxoanion of [(α-B-ZnW9O34)2W2Mn2(H2O)2]8− consists of two Keggin lacunary α-B-ZnW9O34 12− moieties linked via a rhomblike W2Mn2O16 group leading to a sandwich-type structure.

Three polyoxomolybdate compounds, namely {[MII(HL)2]2(Mo8O26)}n (M = Co (1), Ni (2), Zn (3)) (HL, 3-(2-pyridyl)pyrazole), were designed and synthesized under the hydrothermal conditions and characterized by elemental analysis, IR spectroscopy, and TGA. Single-crystal X-ray diffraction analysis results reveal that compounds 1–3 own the isostructural chain structure consisting of the β-[Mo8O26]4− anions, which are linked by M(HL)22+ units via the terminal oxygen atoms. TGA curves show that the organic ligands separate from the related compounds above ca. 673 K.

An 18-membered complex, [Fe(MMSHZ)(DMF)]6 (1) [MMSHZ = N-(methyl-maleamic ester)acylsalicylhydrazine] was synthesized and structurally characterized. There are not only particular geometry configurations of N-terminal groups which result in the unique shape of the centric cavity, but also inter- and intra-molecular interactions assembling adjacent molecules into 2-D framework in complex 1. Temperature-dependent magnetic susceptibility measurements indicate that this complex exhibits significantly antiferromagnetic coupling among the metal centers.

One metalorganic complex [K(cis-syn-cis- dicyclohexyl-18-crown-6)]2[Cu(mnt)2] (mnt = maleonitriledithiolate) has been obtained by the reaction of dicyclohexyl-18-crown-6 with K2mnt and CuCl2·2H2O. The title complex has been characterized by elementary analysis, FT-IR, UV-Vis spectroscopy and x-ray single crystal diffraction. The title complex crystallizes in the triclinic space group P1 with crystallographic data: a = 10.870(6) A, b = 11.536(6) A, c = 12.904(7) A, α = 101.541(10)°, β = 110.573(9)°, γ = 99.441(9)°, V = 1435.2(13) A3, Z = 1, Dcalcd = 1.350 g/cm3, F(000) = 615, R1 = 0.0641, wR2 = 0.1475. It displays one-dimensional chain-like structure formed by [K(cis-syn-cis- dicyclohexyl-18-crown-6)]+ complex cations and [Cu(mnt)2]2- complex anions through N-K-N interactions. Its electrochemical behavior has also been studied by the cyclic voltammetry. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)