Syntheses and Characterization of Three New Compounds Based on Terephthalate and 2‐(2‐Pyridin‐4‐yl‐vinyl)benzimidazole Ligands

Three new compounds based on H₂BDC and PyBImE [H₂BDC = 1,4‐benzenedicarboxylatic acid, PyBImE = 2‐(2‐pyridin‐4‐yl‐vinyl)benzimidazole], namely, [Co(PyBImE)(BDC)(H₂O)₂] ( 1 ), [Co(PyBImE)₂(HBDC)(BDC)_0.5] ( 2 ), and [(HPyBImE)⁺ · (BDC)²–_0.5 · (H₂BDC)_0.5] ( 3 ), were synthesized by hydrothermal methods and characterized by single‐crystal X‐ray diffraction. Compound 1 is a one‐dimensional chain bridged by terephthalate in a bis(monodentate) fashion. In the complex the nitrogen atom from N_BIm and the coordination water molecule complete the coordination sphere. In complex 2 , the dinuclear cobalt units are bridged by terephthalate in a bis(bidentate) fashion into a one‐dimensional chain, but different from complex 1 , the nitrogen atom from N_Py and the oxygen atom from hydrogenterephthalate complete the coordination sphere. Complex 3 is a co‐crystal with PyBImE and H₂BDC in a 1:1 ratio and the transfer of hydrogen atoms leads the complex into a salt. Interesting supramolecular structures are shown due to the hydrogen bonding as well as π ··· π interactions in the three complexes. Thermal and magnetic properties of 1 and 2 were also studied.     

Supramolecular Structures with the 2‐Propyl‐4,5‐dicarboxy‐1H‐imidazole Ligand: Hydrothermal Synthesis,Structures, and Photoluminescence

Self‐assembly of the rigid organic ligand 2‐propyl‐4,5‐dicarboxy‐1H‐imidazole ( L ) with different metal ions (Zn²⁺, Ni²⁺, Cu²⁺, Cd²⁺) led to four new complexes, namely, [M( L )(phen)] [M = Zn ( 1 ); Ni ( 2 ); Cd ( 3 )] and [Cu( L )( 4 )] (phen = 1,10‐phenanthroline). Their structures were determined by single‐crystal X‐ray diffraction analyses, and they were further characterized by elemental analysis, IR spectroscopy, and thermogravimetric analysis. Whereas compounds 1 , 2 , and 3 are discrete units, hydrogen‐bonding interactions play a vital role in these complexes. Compounds 1 and 2 form one‐dimensional (1D) and two‐dimensional (2D) structures through hydrogen‐bondinginteractions with helical character. In 1 , the hydrogen bonds (O–H ··· O) alternately bridge the M^II cations of the discrete units to form a one‐dimensional (1D) infinite helical chain. Complex 2 forms a 2D helical layer through parallel hydrogen bonds (N/O–H ··· O/N) between two adjacent helical chains. In 3 , the hydrogen bonds (N–H ··· O) connect adjacent discrete units into a ten‐membered ring with extension into a one‐dimensional double‐chain supramolecular structure. Complex 4 is a two‐dimensional gridlike (4,4) topological layer which is extended to a 3D network by hydrogen bonding. The solid‐state fluorescence spectrum of complex 3 was determined.     

Syntheses,Structures, and Luminescent Properties of d10 Coordination Polymers with 2‐(4‐Carboxyphenyl)‐imidazo[4, 5‐f]‐1, 10‐phenanthroline and 1, 3‐Benzenedicarboxylate Derivatives

Four Zn^II/Cd^II coordination polymers (CPs) based on 2‐(4‐carboxy‐phenyl)imidazo[4, 5‐f]‐1, 10‐phenanthroline (HNCP) and different derivatives of 5‐R‐1, 3‐benzenedicarboxylate (5‐R‐1, 3‐BDC) (R = NO₂, H, OH), [Zn(HNCP)(5‐NO₂‐1, 3‐BDC)]_n ( 1 ), [Cd(HNCP)(5‐NO₂‐1, 3‐BDC)]_n ( 2 ), [Zn(HNCP)(1, 3‐BDC)(H₂O)₂]_n ( 3 ), and {[Zn(HNCP)(5‐OH‐1, 3‐BDC)(H₂O) · H₂O}_n ( 4 ) were synthesized under hydrothermal conditions. Compounds 1 – 4 were determined by elemental analyses, IR spectroscopy, and single‐crystal and powder X‐ray diffraction. Compounds 1 and 2 are isomorphous, presenting a 4‐connected uninodal (4, 4)‐sql 2D framework with threefold interpenetration, which are further extended into the three‐dimensional (3D) supramolecular architecture through π ··· π stacking interactions between the aryl rings of 5‐NO₂‐1, 3‐BDC. Compared to compound 1 , 3 is obtained by using different reaction temperatures and metal‐ligand ratios, generating a 3D framework with –ABAB– fashion via π ··· π stacking interactions. Compound 4 is a 1D chain, which is further extended into a 3D supramolecular net by hydrogen bonds and π ··· π stacking interactions. The thermogravimetric and fluorescence properties of 1 – 4 were also explored.     

Syntheses,Crystal Structures,and Properties of Lead(II), ­Zinc(II), and Manganese(II) Complexes Constructed from 2, 3, 5, 6‐Tetraiodo‐1, 4‐benzenedicarboxylic Acid

Three new coordination compounds, [Pb(HBDC‐I₄)₂(DMF)₄]( 1 ) and [M(BDC‐I₄)(MeOH)₂(DMF)₂]_n (M = Zn^II for 2 and Mn^II for ( 3 ) (H₂BDC‐I₄ = 2, 3, 5, 6‐tetraiodo‐1, 4‐benzenedicarboxylic acid), were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric (TG) analysis, and X‐ray single crystal structure analysis. Single‐crystal X‐ray diffraction reveals that 1 crystallizes in the monoclinic space group C2/c and has a discrete mononuclear structure, which is further assembled to form a two‐dimensional (2D) layer through intermolecular O–H ··· O and C–H ··· O hydrogen bonding interactions. The isostructural compounds 2 and 3 crystallize in the space group P2₁/c and have similar one‐dimensional (1D) chain structures that are extended into three‐dimensional (3D) supramolecular networks by interchain C–H ··· π interactions. The Pb^II and Zn^II complexes 1 and 2 display similar emissions at 472 nm in the solid state, which essentially are intraligand transitions.     

Poly­[[[(1,10‐phenanthroline‐κ2N,N′)­zinc(II)]‐μ3‐5‐hydroxy­isophthalato‐κ4O,O′:O′′:O′′′] monohydrate]

In the title compound, {[Zn(C₈H₄O₅)(C₁₂H₈N₂)]·H₂O}_n or {[Zn(OH‐BDC)(phen)]·H₂O}_n (where OH‐H₂BDC is 5‐hydroxy­isophthalic acid and phen is 1,10‐phenanthroline), the Zn atoms are coordinated by two N atoms from the phen ligands and by four O atoms from hydroxy­isophthalate ligands in a highly distorted octahedral geometry, with Zn—O distances in the range 2.042 (4)–2.085 (5) Å and Zn—N distances of 2.133 (5) and 2.137 (5) Å. The {[Zn(OH‐BDC)(phen)]·H₂O}_n infinite zigzag polymer forms a helical chain of [Zn₂(OH‐BDC)₂]_n units. Face‐to‐face π–π interactions (3.60–3.75 Å) occur between two phen rings belonging to the same helical chain. Consolidation of the packing structure is achieved by O—H⋯O hydrogen‐bonding interactions between the carboxyl­ate O atoms, the hydroxyl group and the water mol­ecule, forming two‐dimensional sheets.     

Syntheses and Structural Characterization of Four New Silver(I) Complexes with the N,N′(O)‐bidentate Bridging Ligands

Four new bridged silver(I) complexes, namely [Ag₂(μ₂‐teda)(μ₂‐fbc)₂] ( 1 ), [Ag₂(μ₂‐1,6‐dah)₂](bpdc) · 4H₂O ( 2 ), [Ag₂(μ₂‐2‐ap)(2‐ap)(bnb)] · 0.34H₂O ( 3 ), [Ag₂(μ₂‐pyc)₂(2‐apy)₂] · 0.5H₂O ( 4 ), have been synthesized and characterized by elemental analysis and crystallographic methods [fbc = 4‐fluorobenzoate, teda = triethylenediamine ( 1 ); bpdc = biphenyl‐4,4′‐dicarboxylate, 1,6‐dah = 1,6‐diaminohexane ( 2 ); bnb = 3,5‐binitrobenzoate, 2‐ap = 2‐aminopyrimidine ( 3 ); pyc = 3‐pyridinecarboxylate acid, 2‐apy = 2‐aminopyridine ( 4 )]. Complex 1 contains a 1D linear chain paralleling to the c‐axis, whereas in complex 2 silver(I) atoms were bridged by the 1,6‐dah ligand into a zigzag chain, further giving a 1D ribbon by weak Ag ··· Ag interactions. Complex 3 consists of a dinuclear silver(I) [Ag₂(μ₂‐2‐ap)(2‐ap)(bnb)] moiety and a lattice water molecule, forming a 3D network via a number of hydrogen‐bonding interactions such as N–H ··· O, N–H ··· N and C–H ··· O hydrogen bond and other weak interactions such Ag ··· Ag, Ag ··· N, N ··· O as well as O ··· O interaction. Similar to 3 , the asymmetric unit of 4 consists of one dinuclear silver(I) [Ag₂(μ₂‐pyc)₂(2‐apy)₂] moiety and half lattice water molecule, further generating a tetranuclear silver(I) {[Ag₂(μ₂‐pyc)₂(2‐apy)₂]₂ · H₂O} moiety. These moieties construct a 3D supramolecular network structure of 4 through N–H ··· O, O–H ··· O and C–H ··· O hydrogen bonds as well as other weak interactions such as Ag ··· O and N ··· O interactions.     

Co‐crystals based on 1,2,4,5‐Benzenetetracarboxylic Acid: Synthesis,Supramolecular Frameworks and Optical Properties

Two new co‐crystals based on 1,2,4,5‐benzenetetracarboxylic acid, (H₂BETC)(H₄tpim)](NO₃) ( 1 ) and [(H₄BETC)_0.5(H₂BETC)_0.5(HVB4)](H₂O) ( 2 ) [H₄BETC = 1,2,4,5‐benzenetetracarboxylic acid, Htpim = 2,4,5‐tri(4‐pyridyl)‐imidazole, and VB4 = adenine], were synthesized and characterized by elemental analyses, IR spectroscopy, single‐crystal X‐ray diffraction, and X‐ray powder diffraction analysis. Compounds 1 and 2 were further assembled to form 3D supramolecular frameworks with 1D channels by intermolecular C–H ··· O, O–H ··· O, and N–H ··· O hydrogen‐bonding interactions. The results reveal that the structural differences of 1 and 2 may be attributed to different molecular components. Moreover, the UV/Vis and luminescent spectra of ligands and corresponding compounds were briefly investigated.     

Mixed‐ligand Complexes with 2,6‐Pyridinedicarboxylato(2‐) and 4,7‐Diphenyl‐1,10‐Phenanthroline Ligands, [MII(pdc)(DPphen)(H2O)]·H2O (M = Co or Cu). Synthesis,Crystal Structures and Properties

Iso‐type [M^II(pdc)(DPphen)(H₂O]·H₂O compounds (M = Co or Cu, pdc = 2,6‐pyridinedicarboxylato(2‐) ligand and DPphen = 4,7‐diphenyl‐1,10‐Phenanthroline) were synthesized and studied by X‐ray diffraction, thermal and spectral methods. The N,N′‐equatorial bidentate DPphen‐copper(II) chelation imposes a mer‐N(equatorial)+O₂(apical) conformation to pdc in the coordination polyhedron (type 4+1+1). In the Co(II) derivative, the coordination is of type 1+2+2+1 because of a lesser Jahn‐Teller distortion. In the crystals, π,π‐interligand interactions between phen ligands connect the complex molecules in multi‐stacked chains. Aqua···O(carboxyl) H‐bonding interactions reinforce the stacked chains and build double chains in 1D supramolecular structures parallel to the a axis. Non coordinated water connect these structures by H‐bonds.     

Syntheses,Structures, Electrochemistry,and Electrocatalysis of Three Copper(II) Coordination Polymers constructed from 5‐[4‐(1H‐Imidazol‐1‐yl)phenyl]‐1H‐tetrazole

Three coordination polymers (CPs) based on the 5‐[4‐(1H‐imidazol‐1‐yl)phenyl]‐1H‐tetrazole ( HL ) ligand, namely, [Cu(μ₂‐ L )(μ₄‐pbda)(H₂O)] ( 1 ), [Cu₂(μ‐Hbtc)(H₂btc)(μ₃‐OH)(μ₄‐ HL )] ( 2 ) and [Cu₅(μ₃‐ L )(μ₄‐ L )(μ₃‐ip)(μ₃‐OH)(H₂O)₂] · 2H₂O ( 3 ) (H₂pbda = 1,4‐benzenedicarboxylic acid, H₃btc = 1,3,5‐benzenetricarboxylic acid, H₂ip = isophthalic acid) were hydrothermally synthesized and structurally characterized. Complex 1 represents “weave”‐type 2D layers consisting of wave‐like 1D chains and 1D straight chains, which are further connected by hydrogen bonds to form a 3D supramolecular structure. Complex 2 exhibits a uninodal (4)‐connected 2D layer with a point symbol of {4⁴ · 6²}, in which the L ligand can be described as μ₅‐bridging and the H₂btc^– ions display multiple kinds of coordination modes to connect Cu^II ions into 1D “H”‐type Cu‐H₂btc chains. In complex 3 , 2D Cu‐ L layers with two kinds of grids and 1D “stair”‐type Cu‐ip chains link each other to construct a 3D {4¹² · 6³} framework, which contains the pentanuclear subunits. Deprotonated degree and coordination modes of carboxylate ligands may consequentially influence the coordination patterns of main ligands and the final structures of complexes 1 – 3 . Furthermore, electrochemical behaviors and electrocatalytic activities of the title complexes were analyzed at room temperature, suggesting practical applications in areas of electrocatalytic reduction toward nitrite and hydrogen dioxide in aqueous solutions, respectively.     

A fourfold interpenetrating diamondoid three‐dimensional coordination polymer: poly[[[μ2‐1,2‐bis(pyridin‐4‐yl)ethene‐κ2N:N′](μ2‐5‐hydroxyisophthalato‐κ2O1:O3)zinc(II)] 1,2‐bis(pyridin‐4‐yl)ethene hemisolvate]

In the title compound, {[Zn(C₈H₄O₅)(C₁₂H₁₀N₂)]·0.5C₁₂H₁₀N₂}_n or {[Zn(HO‐BDC)(bpe)]·0.5bpe}_n [HO‐H₂BDC is 5‐hydroxyisophthalic acid and bpe is 1,2‐bis(pyridin‐4‐yl)ethene], the asymmetric unit contains a Zn^II atom, one HO‐BDC ligand, one coordinated bpe ligand and half a noncoordinating bpe molecule with crystallographic inversion symmetry. Each Zn^II centre is four‐coordinated by two O atoms from two distinct HO‐BDC ligands and two N atoms from two different bpe ligands in a ZnO₂N₂ coordination environment. The three‐dimensional topology of the title compound corresponds to a fourfold interpenetrating diamondoid coordination polymer network, with the uncoordinated bpe ligands located in the cavities, hydrogen bonded to the main network via the hydroxy group of the HO‐H₂BDC ligand.     

Novel Hydrogen-bonded Three-dimensional Supramolecular Architectures Containing 2D Honeycomb Networks or 2D Grids

Two new supramolecular complexes,[Cu(H_2dhbd)(3-pyOH)(H_2O)]_2·3-pyOH·2H_2O(1)and[Cu_2(dhbd)(dpa)_2-(H_2O)]·6H_2O(2)(H_4dhbd=2,3-dihydroxybutanedioic acid,3-pyOH=3-hydroxypyddine,dpa=2,2'-dipyridylamine),have been synthesized in aqueous solution and characterized by single-crystal X-ray diffraction,elemental analyses,UV-Vis and IR spectra,and TGA analysis.X-ray structural analysis revealed that,through four pairs of strong O…H—O hydrogen bonds,the cyclic dinuclear units in 1 together with four adjacent neighbors are connected into a 2Dhoneycomb network encapsulating free 3-pyOH ligands.Unexpectedly,the water-dimers are fixed in interlayers of2D honeycomb network and act as hydrogen-bond bridging to further extend these 2D networks into 3D hydro-gen-bonded framework.Complex 2 includes interesting 2D grids constructed from chiral dinuclear units throughstrong O…H—O and O…H—N hydrogen bonding,which are extended through other crystallization water mole-cules into three dimension with channels.Variable-temperature magnetic susceptibility measurements for bothcomplexes indicate the presence of weak antiferromagnetic exchange interactions between adjacent copper(Ⅱ)ions.     

Cadmium(II) Complexes with Mixed cis‐Epoxysuccinate and 2,2′‐Bipyridyl‐Like Ligands: Syntheses,Crystal Structures,and Luminescent Properties

Two new Cd^II complexes, [Cd( ces )(phen)]_∞ ( 1 ) and {[Cd( ces )(bpy)(H₂O)](H₂O)}₂ ( 2 ), were prepared by slow solvent evaporation methods from mixtures of cis‐epoxysuccinic acid and Cd(ClO₄)₂ · 6H₂O in the presence of phen or bpy co‐ligand ( ces = cis‐epoxysuccinate, phen = 1,10‐phenanthroline, and bpy = 2,2′‐bipyridine). Single‐crystal X‐ray diffraction analyses show that complex 1 has a one‐dimensional (1D) helical chain that is further assembled into a two‐dimensional (2D) sheet, and then an overall three‐dimensional (3D) network by the interchain C–H ··· O hydrogen bonds. Complex 2 features a dinuclear structure, which is further interlinked into a 3D supramolecular network by the co‐effects of intermolecular C–H ··· O and C–H ··· π hydrogen bonds as well as π ··· π stacking interactions. The structural differences between 1 and 2 are attributable to the intervention of different 2,2′‐bipyridyl‐like co‐ligands. Moreover, 1 and 2 exhibit intense solid‐state luminescence at room temperature, which mainly originates from the intraligand π→π* transitions of aromatic co‐ligands.     

Synthesis,Structures, and Catalytic Properties of Two ­Cobalt(II) Coordination Polymers Based on 5‐Substituted Isophthalate and Flexible Bis(benzimidazole) Co‐ligands

Two new Co^II coordination polymers, [Co(L₁)_0.5(hip)]_n ( 1 ) and [Co(L₂)(mip) · 2H₂O]_n ( 2 ) [L₁ = 1,1′‐(1,4‐butanediyl)bis‐1H‐benzimidazole, L₂ = 1,3‐bis(5,6‐dimethylbenzimidazol‐1‐yl)‐2‐propanol, H₂hip = 5‐hydroxyisophthalic acid, H₂mip = 5‐methylisophthalic acid], were synthesized under hydrothermal conditions and structurally characterized by elemental analysis, IR spectroscopy, and X‐ray single‐crystal diffraction. Complex 1 exhibits a 3D supramolecular network constructed with 2D (4,4) layer by O–H ··· O hydrogen bonding. Complex 2 has 1D ladder‐like chains, which are further assembled into a 3D supramolecular framework by π–π stacking interactions. In addition, fluorescence and catalytic properties of compounds 1 and 2 were investigated in solid state.     

Synthesis,Characterization, and Crystal Structure of Three Coordination Polymers from 5‐(Pyridin‐2‐ylmethyl)aminoisophthalic Acid

Three new complexes: [M(L)(H₂O)] [M = Zn ( 1 ), Co ( 2 ), Ni ( 3 ); H₂L = 5‐(pyridin‐2‐ylmethyl)aminoisophthalic acid] were synthesized under hydrothermal conditions at 180 °C and were characterized by elemental analysis, FT‐IR spectroscopy, single‐crystal X‐ray diffraction, and thermogravimetric analysis (TGA). The results of X‐ray diffraction analysis reveal that complexes 1 – 3 are isostructural and crystallize in the monoclinic system with space group P2₁/c. Each of the complexes displays a (3,3′)‐connected two‐dimensional (2D) wave‐like network with (4,8²) topology, within which five‐membered uncoplanar N,N‐chelated metallacycles are shaped. Delicate N–H ··· O and O–H ··· O hydrogen bonding interactions exist in complexes 1 – 3 . Adjacent 2D layers are linked by intermolecular interactions, resulting in the construction of extended metal‐organic frameworks (MOFs) in complexes 1 and 2 .     

Syntheses,Characterization, and Electrochemical Lithium‐Ion Storage Properties of Two Cobalt(II) Coordination Polymers Containing 5‐Hydroxyisophthalic Acid and Bis‐benzoimidazole Ligands

Two cobalt(II) coordination polymers, namely {[Co(HO‐BDC)(bbe)] · (H₂O)}_n ( 1 ), and {[Co(O‐BDC)(bbp)] · (H₂O)}_n ( 2 ) (HO‐H₂BDC = 5‐hydroxyisophthalic acid, bbe = 1, 2‐bis(benzoimidazol‐2‐yl)ethane, and bbp = 1, 3‐bis(benzoimidazol‐2‐yl)propane) were synthesized under hydrothermal conditions, and characterized by elemental analyses, IR spectroscopy, single‐crystal X‐ray diffraction, and thermogravimetric analyses. Compound 1 is a 1D chain, whereas 2 is a (3, 3)‐connected 2D network with (6³) topology. These two 1D and 2D complexes are further connected by hydrogen bonds to form the 3D supramolecular architectures. The electrochemical lithium‐ion storage properties of the as‐made Co₃O₄ by calcination of 1 are investigated in detail.     

A 2‐fold Interpenetrated Framework based on Tetranuclear Heterometallic Cluster: Synthesis,Structure and Magnetic Properties

A 2‐fold parallel interpenetrated polymer, ZnCo(OH)(pheno)(p‐BDC)_1.5·H₂O ( 1 ) (pheno = phenanthrene‐9,10‐dione; p‐BDC = 1,4‐benzenedicarboxylate) has been prepared by hydrothermal synthesis and structurally characterized by IR, elemental analysis, ICP and single crystal X‐ray diffraction. Complex 1 crystallizes in the orthorhombic space group Pbca and affords a three‐dimensional (3D) six‐connected α‐Po network. The magnetic behavior for 1 was studied in the temperature range of 1.8‐300 K.     

Hydrogen bonding in two benzene‐1,2‐diaminium pyridine‐2‐carboxylate salts and a cocrystal of benzene‐1,2‐diamine and benzoic acid

The isostructural salts benzene‐1,2‐diaminium bis(pyridine‐2‐carboxylate), 0.5C₆H₁₀N₂²⁺·C₆H₄NO₂^?, (1), and 4,5‐dimethylbenzene‐1,2‐diaminium bis(pyridine‐2‐carboxylate), 0.5C₈H₁₄N₂²⁺·C₆H₄NO₂^?, (2), and the 1:2 benzene‐1,2‐diamine–benzoic acid cocrystal, 0.5C₆H₈N₂·C₇H₆O₂, (3), are reported. All of the compounds exhibit extensive N—H…O hydrogen bonding that results in interconnected rings. O—H…N hydrogen bonding is observed in (3). Additional π–π and C—H…π interactions are found in each compound. Hirshfeld and fingerprint plot analyses reveal the primary intermolecular interactions and density functional theory was used to calculate their strengths. Salt formation by (1) and (2), and cocrystallization by (3) are rationalized by examining pK_a differences. The R₂²(9) hydrogen‐bonding motif is common to each of these structures.     

New Examples of Metal Coordination Architectures of 3,3′,4,4′‐Biphenyltetracarboxylic Acid – Syntheses,Crystal Structures,and Physical Properties

Four new metal‐organic frameworks [Cu₂(2,2′‐bipy)₂(ox)(H₂O)₂]·(H₂bptc) ( 1 ), [Cu(bptc)_0.5(phen)(H₂O)]·H₂O ( 2 ), Co₂(bptc)(bmb)_1.5 ( 3 ) and [Cd₂(bptc) (bmb)]·3H₂O ( 4 ) (H₄bptc = 3,3′,4,4′‐biphenyltetracarboxylic acid, ox = oxalate, phen = 1,10‐phenanthroline, 2,2′‐bipy = 2,2′‐bipyridine and bmb = 4,4′‐bis((1H‐imidazol‐1‐yl)methyl)biphenyl), were obtained by reactions of the corresponding metal salts with H₄bptc and N‐containing auxiliary ligands and their structures were determined by single‐crystal X‐ray diffraction. The results reveal that 1 has a 0‐D structure consisting of discrete ionic entities, while 2 features a 1‐D ladder structure. Additionally, there exist π‐π stacking and intermolecular hydrogen‐bonding interactions in 1 and 2 , respectively, forming 3‐D supramolecular structures. In 3 ‐ 4 , undulating 2‐D metal‐bptc layer structures are formed with two different coordination modes of bptc carboxylate groups, respectively, which are further extended by bmb into 3‐D structures. Magnetic properties of 1 and 3 have been studied. The photoluminescence property of 4 has also been investigated. Moreover, nonlinear optical measurements showed that 4 displayed a second‐harmonic‐generation (SHG) response of 0.7 times of that for urea.     

Synthesis,Structures, and Photocatalytic Properties of Zinc(II) and Cobalt(II) Supramolecular Complexes Constructed with Flexible Bis(thiabendazole) and Dicarboxylate Linkers

Three coordination complexes, namely, [Zn(btbp)(3‐npa)]_n ( 1 ), [Co(btbh)(3‐npa)]_n ( 2 ), and {[Co(btbb)(5‐nipa)(H₂O)] · H₂O}_n ( 3 ) (btbp = 1,3‐bis(thiabendazole)propane, btbh = 1,6‐bis(thiabendazole)hexane, btbb = 1,4‐bis(thiabendazole)butane, 3‐H₂npa = 3‐nitrophthalic acid and 5‐H₂nipa = 5‐nitroisophthalic acid) were synthesized under hydrothermal conditions and characterized by physicochemical and spectroscopic methods as well as by single‐crystal X‐ray diffraction. Complex 1 features a fascinating meso‐helical chain, which is further extended into a 2D supramolecular framework involving π ··· π stacking interactions. Complexes 2 and 3 show dinuclear structures. Complex 2 is further connected through C–H ··· O hydrogen bonding interactions to afford a 2D supramolecular layer, whereas complex 3 is further extended to a rare 2‐nodal (3,4)‐connected supramolecular sheet with a point symbol of {3.4².5.6.7}₂{3.8²} by O–H ··· O hydrogen bonding interactions. The electrochemical behaviors of the two cobalt complexes 2 and 3 were reported. Moreover, the luminescent properties for 1 and the photocatalytic properties for the complexes were investigated.     

Syntheses,Crystal Structures,and Photocatalytic Activities of Three Copper Coordination Polymers Based on Bis(1H‐imidazol‐4‐yl)benzene/3‐(2‐Pyridyl)pyrazole

Three copper(II) coordination polymers (CuCPs), namely, [Cu_0.5(1,4‐bib)(SO₄)_0.5]_n ( 1 ), {[Cu(1,3‐bib)₂(H₂O)] · SO₄ · H₂O}_n ( 2 ), and [Cu(bpz)(SO₄)_0.5]_n ( 3 ), were assembled from the reaction of three N‐donors [1,4‐bib = 1,4‐bis(1H‐imidazol‐4‐yl)benzene, 1,3‐bib = 1,3‐bis(1H‐imidazol‐4‐yl)benzene, and Hbpz = 3‐(2‐pyridyl)pyrazole] with copper sulfate under hydrothermal conditions. Their structures were determined by single‐crystal X‐ray diffraction analyses and further characterized by elemental analyses (EA), IR spectroscopy, powder X‐ray diffraction (PXRD), and thermogravimetric analyses (TGA). Structure analyses reveal that complex 1 is a 3D 6‐connected {4¹² · 6³}‐ pcu net, complex 2 is a fourfold 3D 4‐connected 6⁶‐ dia net, whereas complex 3 is a 1D snake‐like chain, which further expanded into 3D supramolecular architectures with the help of C–H ··· O hydrogen bonds. Moreover, the photocatalytic tests demonstrate that the obtained CuCPs are photocatalysts in the degradation of MB with the efficiency is 86.4 % for 1 , 75.3 % for 2 , and 91.3 % for 3 after 2 h, respectively.