•Investigations of counter anion effect on the ligand behavior of flexible 2-(pyridine-2-ylthio)pyrimidine (Pypm) in its transition metal complexes are conducted and discussed.•The role of the interesting and common intramolecular N···C contact of Pypm ligand in constructing the transition metal complexes is observed and systemically compared with those of other analogous ligands.•This work may provide further insight into the supramolecular chemistry of transition metal complex derived from this type of angular pyridyl-based sulfide ligands.A new multidentate ligand 2-(pyridin-2-ylthio) pyrimidine (abbreviated as Pypm) reacts with silver nitrate, silver trifluoroacetate and copper dichloride, obtaining coordination polymers [Ag(Pypm)(NO3)]∞ (1), [Ag(Pypm)(CF3COO)]∞ (2), and dinuclear [Cu2(Pypm)2(Cl)4] (3), respectively. In complexes 1 and 2, the Pypm ligand takes an unvaried nonplanar configuration with two aromatic rings in an orthogonal orientation, exhibiting a N,N’-μ2-bridging mode linked to separated Ag(I) ions. Interesting intramolecular Npyrimidyl···Cpyridyl contact occurs and stabilizes the nonplanar configuration of Pypm in supramolecular architectures of 1–2. Different coordination abilities and steric geometries between NO3− (in 1) and CF3COO− (in 2) exhibit subtle tuning on the forming of homochiral helix structure in 1 and double-bridged chain in 2. While, in copper(II) complex 3 Pypm takes a κ2N,N-chelating mode to combine the η: η: μ2-bridging Cl− to form a dinuclear complex. The effect of counter anion on construction of a supramolecular architecture and the ligand behavior of the angular-shaped pyridyl-based sulfide ligand are observed and discussed.Silver(I) and copper(II) complexes derived from a newly synthesized 2-(pyridine-2-ylthio)pyrimidine (Pypm) were obtained and characterized. The effect of counter anion on construction of a supramolecular architecture and the ligand behavior of the angular-shaped pyridyl-based sulfide ligands are observed and discussed.Download high-res image (48KB)Download full-size image

Here we developed a facile solvent-assisted ligand exchange method for synthesizing thioether-containing hybrid metal–organic frameworks (MOFs) that cannot be made using direct synthesis. Such a tailored approach provides an alternative method to achieve thioether-based MOFs and its oxidation-decorated materials. These materials showed the ability to take up heavy metals from solution and the ability to capture CO2.

•New example of constructing functional coordination polymer with secondary donor methylthio group.•Guest exchange and interesting Hg(II) absorb ability from solution are investigated.•New method to construct functional materials with potential application.Dipyridyl sulphide ligands 4-(pyridin-4-ylmethylthio)pyridine (abbreviated as L1) and 3-(pyridin-4-ylmethylthio)pyridine (abbreviated as L2) have been designed and used as μ-N,N-bridging linkages to construct coordination polymers with free –S–CH2– groups as secondary donor sites. By use solvent control method, coordination polymers {[Ag3SO4(L1)3](Cl)·4.5H2O}∞(1), {[Ag2SO4(L1)2]·6H2O·2CH3OH}∞(2), {[Ag2SO4(L2)2]·H2O}∞(3) and {[Ag4(SO4)2(L2)4]·5H2O}∞(4) with different architectures were obtained. Complexes 1, 3 and 4 feature 1D channel with different sizes and structures. Complex 1 exhibits guest exchange by THF and 1,4-dioxane, and Hg2+ sorption ability from solution due to its relative larger channel and available bonding sites of –S– exposed to the channel region. All complexes have been characterized through single-crystal and powder X-ray diffraction (PXRD), FT-IR spectra, X-ray photoelectron spectroscopy (XPS), elemental and thermogravimetric analyses. The guest exchange and Hg2+ sorption were monitored and identified, and the structure-property relationship of coordination polymers 1–4 are discussed.Coordination polymers of silver(I) sulfate with secondary donor sites are shown guest exchange property and Hg2+ absorb ability from solution. This work provides a new method to construct functional materials with potential application.Download high-res image (211KB)Download full-size image

•Two Pt(II) complexes 7a,b with indolin-2-one derivatives were synthesized.•7a,b exhibited stronger cytotoxicity against three cell lines than the corresponding ligands.•Treatment of HCT-116 cells with 7a,b increased sub-G1 population in cell cycle profiles.•Treatment with 7a,b led to the cleavage of PARP1, caspases 3, 7 and 9 in HCT-116 cells.•The new complexes induced apoptosis in cancer cells possibly through non-covalently binding to DNA.Two new platinum(II) complexes 7a and 7b with methyl hydrazinecarbodithioate derivatives of indolin-2-one have been prepared and characterized by single-crystal X-ray diffraction, NMR spectroscopy and mass spectrometry. Antiproliferative activity of the two complexes and their ligands 6a and 6b against HCT-116, MCF-7 and MDA-MB-231 cell lines was determined by the MTS assay. Complexes 7a and 7b exhibited stronger antiproliferative activity against three cell lines than compounds 6a and 6b (IC50, 1.89–5.60 versus 6.52–35.13 μM). Moreover, treatment of HCT-116 cells with the complexes resulted in an obvious sub-G1 peak by cell cycle profile analysis, and an increase of cleaved PARP1 and caspases 3, 7, and 9 by immunoblotting analysis. Live cell imaging showed that nucleus shrinkage and condensation started to appear when MCF-7 cells were treated with 7a for 8 h. Fluorescent spectrophotometric analysis revealed that the complexes physically associated with calf thymus DNA. Competitive DNA binding assays uncovered that the complexes non-covalently bind to DNA. Taken together, our results indicated that the two new platinum(II) complexes 7a and 7b non-covalently bind to DNA with high affinity and exhibit cytotoxicity against cancer cells by inducing apoptosis.Coordination of 6a,b with Pt(II) resulted in complexes 7a,b with enhanced cytotoxicity. The complexes exerted cytotoxic effects towards cancer cells by inducing apoptosis, possibly through non-covalently binding to DNA.Download high-res image (120KB)Download full-size image

We report herein the efficient synthesis of alkynyl-protected silver nanoclusters in terms of macrocycle-assisted bulk-to-cluster-to-nanoparticle transformation. Different substituted phenylacetylide ligands are applied to stabilize the silver nanoclusters by metal–carbon bonds and meanwhile determine the size of silver nanoclusters.

Yolk–shell architectures have attracted extensive attention owing to their unique structure and infusive applications. MoS2 is regarded as one of the most promising catalytic materials for hydrogen evolution by the splitting of water. In this work, a simple self-template solvothermal approach is developed for the synthesis of novel MoS2 yolk–shell microspheres with a hierarchical porous structure by reacting MoO2 microspheres with L-cysteine. A dissolutionrecrystallization formation mechanism is proposed for the MoS2 yolk–shell microspheres. Owing to structural superiority, the new material architecture exhibits improved photoelectrochemical properties, including efficient hydrogen evolution reaction catalytic activities, a high photocurrent density, a small overpotential, and a low charge-transfer resistance.

Hybrid metal/semiconductor nanostructures have been synthesized by a general in situ reaction between weakly reductive metal oxides and oxidative metal precursors without foreign reducing agents and stabilizing agents. These hybrid materials exhibit excellent activity for photocatalytic generation of benzyl compounds.

•Three isomeric pyridyl-pyrazinyl ketones were systemically synthesized.•Nine group 11 and 12 complexes with ketone or hydrated forms were observed.•In-situ nucleophilic reaction mechanism involving the carbonyl group was probed.A series of Cu(II), Ag(I), Zn(II) and Cd(II) complexes of new pyridyl-pyrazinyl ketones 2-pyridinyl-2-pyrazinylmethanone (abbreviated as L1), 3-pyridinyl-2-pyrazinylmethanone (L2) and 4-pyridinyl-2-pyrazinylmethanone (L3) has been synthesized and characterized by single crystal X-ray analysis. L1 can takes not only its neat ketone form in [Ag(L1)(NO2)]∞ (1), but also the gem-diol form (L1a) in [Ag(L1a)(CF3CO2)]∞ (2) and [Cu(L1a)2](BF4)2·4H2O (3) via in-situ metal-promoted nucleophilic reaction. L2 and L3 preferentially adopt their ketone forms in zinc(II) and cadmium(II) complexes [Zn(L2)2Cl2] (4), [Cd(L2)2(NO3)2(H2O)2] (5), {[Cd(L2)2(H2O)2](BF4)2·4H2O}∞ (6), {[Cd(L2)2(H2O)2](ClO4)2·4H2O}∞ (7), [Cd(L3)2(H2O)4](NO3)2 (8) and {[Cd4(L3)4(ClO4)2](ClO4)6⋅13H2O}∞ (9). The ligand behavior of L1–L3 in complexes 1–9 are compared to that of di-2-pyridinylmethanone and its positional isomers. The metal-promoted nucleophilic reaction mechanism involving the carbonyl group in coordination complexes of the pyridyl ketone family is probed and discussed. Supramolecular architectures of complexes 1–9 with the various ketones are also observed and discussed.New isomeric pyridyl-pyrazinyl ketonic ligands 2-pyridinyl-2-pyrazinylmethanone, 3-pyridinyl-2-pyrazinylmethanone and 4-pyridinyl-2-pyrazinylmethanone have been synthesized, and their coordination behavior in a series of group 11 and 12 complexes is probed and discussed.

•The sensor exhibited low detection limit (0.064 pM) and wide linear range to angiogenin (0.1 pM–5 nM).•The proposed electrochemical aptasensor is very simple, cost-effective, highly sensitive.•The sensor provides a promising strategy for the cancer diagnosis in medical application in the future.Herein, a label-free and highly sensitive electrochemical aptasensor for the detection of angiogenin was proposed based on a conformational change of aptamer and amplification by poly(diallyldimethyl ammonium chloride) (PDDA)-functionalized graphene/gold nanoparticles (AuNPs) composites-modified electrode. PDDA-functionalized graphene (P-GR) nanosheets as the building block in the self-assembly of GR nanosheets/AuNPs heterostructure enhanced the electrochemical detection performance. The electrochemical aptasensor has an extraordinarily sensitive response to angiogenin in a linear range from 0.1 pM to 5 nM with a detection limit of 0.064 pM. The developed sensor provides a promising strategy for the cancer diagnosis in medical application in the future.

4-(4-(Nitromethyl)benzylthio)pyridine (abbreviated as L), a ligand bearing 4-pyridyl and nitrobenzene groups, functions as a monodentate ligand and reacts with cobalt(II) chloride and silver(I) perchlorate, leading to new complexes [Co(L)2]Cl2 (1) and [Ag(L)2]ClO4 (2), respectively. Ligand L and complexes 1 and 2 were characterized through X-ray diffraction, IR spectroscopy and elemental analyses. The coordination geometry of Co(II) and Ag(I) exhibit a slightly-distorted tetrahedron and trigonal planar geometry, respectively. The structures of Ligand L [Monoclinic, P21/c, a = 7.8041(3) Å, b = 20.7401(8) Å, c = 7.2625(3) Å, α = 90°, β = 97.946(3)°, γ = 90°], Complex 1 [Triclinic, P-1, a = 16.2634(14) Å, b = 12.4102(5) Å, c = 13.6324(7) Å, α = 102.733(3)°, β = 95.632(3)°, γ = 99.480(3)°], and Complex 2 [Monoclinic, P21/c, a = 7.6144(6) Å, b = 12.8989(12) Å, c = 28.052(2) Å, α = 90°, β = 92.308(4)°, γ = 90°] reveal several different types of intermolecular interactions, such as Ag···O, π-stacking interactions, and C–H···X (X=O, S, halogen) interactions.

Seven coordination polymers (CPs) based on a new multidentate di-2-pyrazinylsulfide (DpzS) ligand and various anions, namely {[Ag3(DpzS)2(ClO4)2](ClO4)}∞ (1), [Ag3(DpzS)2(CF3SO3)3]∞ (2), {[Ag3(DpzS)2(CF3SO3)(H2O)2](CF3SO3)2·H2O}∞ (3), [Ag2(DpzS)(NO3)2(H2O)]∞ (4), [Ag(DpzS)(NO2)]∞ (5), [Ag2(DpzS)(NO2)2]∞ (6) and [Ag2(DpzS)(C2F5CO2)2]∞ (7), have been synthesized and fully characterized by IR spectroscopy, elemental analyses, single crystal X-ray diffraction and powder X-ray diffraction. In 1–7, the DpzS ligand exhibits diverse coordination modes with various silver(I) salts, yielding fascinating 2-D and 3-D topological frameworks. The effect of the anion, such as the size and geometry, on the structural diversities of 1–7 has been discussed. In addition, the role played by anion–π(pyrazinyl) interaction in the supramolecular assembly of 1–7 has also been studied.

Four pure polymorphs (I–IV) and a monohydrate of 1-nitro-4-(4-nitrophenylmethylthio)benzene (abbreviated as NNB) were readily obtained in bulk quantities through a solvent-control strategy. A total of 15 common solvents were used to explore the crystallization behaviour of NNB. Forms II and IV and the monohydrate exhibit solvent-dependent polymorphic selectivity. Form I can be preferentially crystallized from solvents with high dielectric constants, while III is obtainable from solvents with low dielectric constants. All of the forms were characterized via single-crystal X-ray determination, and the rationalization of structural features is discussed. Phase behaviours of the polymorphs were observed through differential scanning calorimetry (DSC) and powder X-ray diffraction. This study may contribute to the strategic discovery and development of a desirable polymorph of any organic drug substance via solvent control.

•A novel secondary carbinol form of di-3-pyridylmethanone was observed.•The metal complexes of the secondary carbinol form were characterized.•New one-pot insitu method to synthesize complex of DPK family was reported.Cadmium(II) trifluoroacetate and silver(I) pentafluoropropionate complexes with the secondary carbinol form of di-3-pyridylmethanone were successfully produced through one-pot insitu method in the presence of aluminum powder and potassium fluoride under mixed-solvent thermal condition. Such one-pot insitu method is the first example to synthesize a metal complex with a secondary carbinol form of di-pyridyl ketone family.Two new metal complexes with a novel secondary carbinol form of di-3-pyridylmethanone were successfully obtained through one-pot insitu method under solvent-thermal condition.

A series of silver(I) complexes bearing the V-shaped di-4-pyridyl sulfone-N,N′-dioxide ligand (abbreviated as L), namely [Ag(L)(NO3)(H2O)]∞ (1), [Ag(L)(CF3SO3)]∞ (2), [Ag(L)(CF3CO2)]∞ (3), [Ag(L)(C2F5CO2)]∞ (4) and {[Ag(L)](ClO4)}∞ (5), and the manganese(II) complex [Mn(L)2(H2O)4](ClO4)2 (6) and the zinc(II) complex [Zn(L)2(H2O)4](ClO4)2 (7) of L have been synthesized and characterized. Under the tuning effect of anions with different coordination capacities and steric bulk, the semi-rigid ligand L exhibits versatile μ2-, μ3- and μ4-bridging modes with the N-oxide and/or sulfonyl O atoms functioning as bonding sites to form a coordination chain structure in complex 1, isostructural nets in 2–4, and a three-dimensional framework in 5. The isostructural mononuclear complexes 6 and 7 exhibit the η1–ON-oxide bonding mode of L. Unusual lone-pair aromatic contacts and anion–π interactions result in supramolecular aggregations of complexes 1–7. The FT-IR spectra and luminescent properties of these complexes have been observed and discussed.The semi-rigid bi-4-pyridyl sulfone-N,N′-dioxide ligand functions as a flexible linkage in a series of Ag(I), Mn(II) and Zn(II) complexes, which exhibit distinct coordination motifs depending upon the cooperative effect of the metal ion and counter anion present.

•New complexes with the same starting materials were successfully achieved.•Solvent and/or counter anion play a key role for complex formation.•Semi-rigid bi-pyrimidinyl sulfide takes an interesting unvaried configuration.The silver(I) complexes {[Ag(DprS)(CH3CN)](ClO4)}∞ (1) with a ladder-like motif and [Ag2(DprS)(CF3CO2)2]∞ (2) with a two-dimensional net were respectively obtained through solvent medium tuning effect (DprS = di-pyrimidinyl sulfide), while complex {[Ag3(DprS)4(C2F5CO2)](CF3SO3)2·H2O}∞ (3) was achieved as a tape-like coordination motif in the presence of mixed counter anions. In 1–3, even in the crystalline state of the neat form DprS, each DprS molecule takes an unvaried non-planar configuration stabilized by intramolecular Npyrimidinyl⋯Cpyrimidinyl contact. Complexes 1–3 and the DprS ligand were fully characterized through single-crystal X-ray diffraction, elemental analysis, FT-IR spectroscopy and luminescent emission measurement. The effect of the choice of solvent and anion on the structure is discussed.Three new Ag(I) complexes of di-pyrimidinyl sulfide with different topological coordination motifs were readily achieved through anion and/or solvent medium tuning effect, wherein the ligands take an unvaried ligation mode with a non-planar configuration.

Hybrid metal/semiconductor nanostructures have been synthesized by a general in situ reaction between weakly reductive metal oxides and oxidative metal precursors without foreign reducing agents and stabilizing agents. These hybrid materials exhibit excellent activity for photocatalytic generation of benzyl compounds.

We report herein the efficient synthesis of alkynyl-protected silver nanoclusters in terms of macrocycle-assisted bulk-to-cluster-to-nanoparticle transformation. Different substituted phenylacetylide ligands are applied to stabilize the silver nanoclusters by metal–carbon bonds and meanwhile determine the size of silver nanoclusters.