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In this work, a novel compound 2‐(3,5,6‐trichloro‐1,4‐benzoquinon‐2‐yl)‐neo‐fused hexaphyrin has been prepared from tetrachloroquinone and neo‐fused hexaphyrin through a substitution reaction. The chemical structure of the compound has been characterized by nuclear magnetic resonance (NMR), high‐resolution mass spectrum, UV–Vis spectrum, and X‐ray diffraction. The crystal structure reveals that the quinonyl unit is almost coplanar with the adjacent N‐confused pyrrole unit. Because of the cooperative effect of extended conjugation and the intramolecular charge transfer effect related to the strong electron‐withdrawing character of the quinonyl unit, the absorption of 2 is dramatically extended to ca. 1280 nm. [ABSTRACT FROM AUTHOR]

[Cu2(H4L)(OCH3)(H2O)] · 2MeOH (1) has been synthesized from the reaction of 2-hydroxy-5-methylisophthalaldehyde, tris(hydroxymethyl)aminomethane and copper(II) perchlorate in methanol with the Schiff-base polyhydroxyl ligand (H4L)3− formed in situ. Single-crystal X-ray structure analysis of 1 reveals a binuclear structure with Cu(II) asymmetrically bridged by a methoxo and a phenoxo group with Cu–O–Cu bridging angles of 102.93(7)° and 100.17(7)°, respectively. The binuclear Cu(II) moieties utilize the coordinated and noncoordinated alkoxyl groups for formation of intermolecular hydrogen bonds, thus affording a 3-D supramolecular structure. Variable temperature magnetic measurements reveal strong antiferromagnetic coupling in 1 with the 2J-value of −729 cm−1, which was mediated cooperatively by the methoxo and phenoxo bridges. Magneto-structural correlations are discussed based on the crystal structure. [ABSTRACT FROM PUBLISHER]

Two complexes of zinc (II) with mixed-ligand, [Zn2(phen)2(HL1)2] (ClO4)2 (1) and [Zn2(phen)2(HL2)2] (ClO4)2(2) (H2L1&z.dbnd6;N–(2-hydroxybenzyl) ethanolamine and H2L2=N–(2-hydroxybenzyl) propanolamine), and another zinc complex ZnL1 (3) were synthesized and characterized by elemental analysis, IR spectra, thermal analysis, fluorescence and 1H NMR. The crystal structure of (1) has a centrosymmetric di-phenoxo-bridged dizinc (II) core and each zinc center is laid in a slightly distorted trigonal bipyramidal geometry. A 2D supramolecular structure is formed approximately along bc plane in terms of the action of multiple N–H⋯O and O–H⋯O hydrogen bonds between the (HL1)− ligands and the π⋯π stacking interactions between the phenanthroline ligands. Thermal behavior, studied by TG and DTA in nitrogen atmosphere, indicates that phen is eliminated at higher temperature than (HL1)− and (HL2)−. Several possible mechanisms for the fluorescence quenching of the metal complexes are proposed. [Copyright &y& Elsevier]

The acylation of 5-aryl dipyrromethanes afforded products with interestingly rich substitution modes, i.e. , α- and β-monoacylated (modes a and b ), and α, α′-, α, β′- and β, β′-diacylated (modes c – e ). Especially, the β- and β, β′-acylation modes are unprecedented. And most of these products can be synthesized at a gram scale. The anisoyl substituted 5-(4-cyanophenyl) dipyrromethanes ( 1a – 1e ) were oxidized with DDQ. Thus, 1a and 1b afforded the corresponding dipyrrins 1a-DPR , and 1b-DPR . More interestingly, the diacylated ones 1c – 1e could not be oxidized by DDQ. Instead, 1c-OH – 1e-OH were obtained with a hydroxyl group attached to the 5-position. 1a-DPR – 1e-OH were further developed as fluorescence turn-on Zn 2+ probes. 1d-OH showed the highest sensitivity, with a detection limit of 1.5 × 10 −8 M, and it was successfully applied in Zn 2+ imaging in Hela cells. Furthermore, single crystals of two Zn 2+ complexes were obtained and analyzed by X-ray diffraction. [ABSTRACT FROM AUTHOR]

Highlights: [•] Combination of the bulky diphenylamino and 9-anthryl units afforded TICT based fluorescence “turn-on” hydrazine probes. [•] Compared with the aldehyde group, the dicyanovinyl group was demonstrated to be a better recognition unit. [•] The TICT mechanism was investigated by theoretical calculations, viscosity dependent fluorescence, and fluorescence decay behaviour. [Copyright &y& Elsevier]

The design and syntheses of porphyrin-basedligands are attractivefor creating coordination assemblies with novel structures and intriguingproperties. In this work, we designed and synthesized a novel porphyrin-basedligand 5,10,15,20-tetrakis(4,4′-dipyridylaminophenylene)porphyrin(TDPAP, H2L) by the introduction of four peripheral 4,4′-dipyridylaminemoieties to a porphyrin platform. Starting from this novel ligand,the protonated form of the ligand H4LCl2·2CH3OH·2H2O (1) and four coordinationpolymers [Mn(III)Mn(II)LCl3(DMF)]n(2), [Cu4L(CH3COO)5(HCOO)(CH3COOH)(H2O)3]n·nCH3COOH·nH2O (3), [Zn3L(CH3COO)4]n(4), and [Cd2H2L(CH3COO)4]n·nDMF·nCH3COOH·2nH2O (5) were synthesized. Single crystal X-ray diffraction analyses revealedthat a rich structural diversity was observed for these compoundsdue to the coordination of the multiple peripheral pyridines as wellas the porphyrin core. 1displays a hydrogen bonded one-dimensional(1D) structure composed of [(H2O)2Cl2]2–moieties. Complex 2shows interpenetratedtwo-dimensional (2D) coordination networks, which are further linkedby π···π stacking interactions to afforda three-dimensional (3D) structure. 3shows a 2D sheetcomposed of 50- and 70-membered metallomacrocycles. In complex 4, 1D zigzag coordination chains were generated and furtherlinked to form a 2D structure. Complex 5has a stairlike2D structure formed by the linkage of 1D coordination chains throughthe bridging of binuclear [Cd2(CO2)4] subunits. In these compounds, TDPAP shows a unique coordinationbehavior. It may bind 4–7 metal centers, and it demonstratesconformational flexibility and the ability to form intermolecularhydrogen bonds and π···π interactions,which contribute to the formation of novel supramolecular structures.On the basis of the novel structures, the solid state emissions ofthe compounds were also investigated. [ABSTRACT FROM AUTHOR]

The design and syntheses of novel ligands are essentialfor developingcoordination compounds with novel structures and interesting properties.In this work, we designed and synthesized a novel ligand bis(4,4′-dipyridylaminophenylene)butadiyne(L) by attaching two 4,4′-dipyridylamine moietiesto a flexible butadiyne linker. Starting from this novel ligand, sevencoordination polymers [Zn2L(HCOO)3(OH)]n(1), [Cd2L2Cl4]n·3nDMF·3nH2O (2), [CdLBr2]n(3), [Cd6L3(SO4)6]n·4nMeCN (4), [Hg2LBr4]n·3nCH2Cl2·nH2O (5), [Cu2LI2]n·0.5nCH2Cl2(6), and [Ag2L(H2O)2]n(NO3)2n·2nH2O (7) were synthesized.Single-crystal X-ray diffraction analyses revealed that two formsof the ligand crystals, Land L·0.5DMFpresent straight and bent conformations, respectively, because ofthe flexibility of the butadiyne unit. A rich structural diversitywas observed for its d10metal complexes. Complexes 1and 5present ladder-like structures. In complexes 2and 4, the ligand molecules are linked by metalatoms to afford 3D supramolecular structures. It is noteworthy thatthe 3D structure of complex 4consists of interestinginfinite {Cd6(SO4)6}∞chains, whereas complexes 3, 6, and 7exhibit 2D network structures. Interestingly, in the crystalof complex 7, each ligand links four metal ions and eachAg ion bridges two ligands, leading to the formation of undulated2D sheets with large cavities composed of 66-membered metallomacrocycles,which are interpenetrated by three other such 2D sheets, affordinga 4-fold interpenetrated structure. In summary, the complex structuresare dependent on the metal ions and the anions. In addition, the flexibilityof the butadiyne moiety provides additional means for modulating thestructures. Solid state photoluminescence of the free ligand and thecomplexes shows emission maxima within the range of 420–515nm, which can be modulated by the conformations of the ligand in additionto the variation of the metal ions and anions, and the introductionof the butadiyne unit has a bathochromic effect. [ABSTRACT FROM AUTHOR]

Self-assembly of N,N,N′,N′-tetra(4-pyridyl)-1,4-phenylenediamine (L1) and N,N-di(2-pyridyl)-N′,N′-di(4-pyridyl)-1,4-phenylenediamine (L2) with MX2 (M = Zn, Cd, and Hg; X = Cl, Br, and I) generated novel supramolecular structures with a rich structural diversity. In the crystal of L1, all pyridyl rings are involved in intermolecular π···π stacking and T-shaped C−H···π interactions to form a two-dimensional (2D) network. [CdL1Cl2]n·nH2O (4), [CdL1I2]n (6), [HgL1Cl2]n (7), [HgL1Br2]n (8), [Cd4(L2)4Cl8]n·2nDMF (13), [CdL2Br2]n (14), [CdL2I2]n (15), and [HgL2Cl2]n·0.5nDMF (16) are coordination polymers. In complex 4, L1 utilizes all its pyridyl nitrogens to coordinate with Cd(II) centers to afford an unprecedented three-dimensional (3D) binodal (3,4)-connected network with the Schläfli symbol of (8.102)2(84.102). Complexes 6, 7, 8, 14, and 15 have zigzag or centipede-like 1D coordination structures. For complex 13, each Cd has an octahedral coordination environment, and the Cd centers are linked by dichloro-bridges to form interesting infinite (CdCl2)∞ chains, which are further bridged by L2 ligands to form a 2D coordination network. Crystal of 16 has a one-dimensional (1D) chain structure. The chains are arranged in an alternate up−down−up mode, with all the pyridyl rings involved in π···π stacking interactions to afford a 3D structure which consists of hexagonal channels along the c-axis. [Hg2(L2)2Br4]·H2O (17) and [Hg2(L2)2I4]·H2O (18) have binuclear coordination moieties, which are linked with water molecules by hydrogen bonds to form 1D structures. From these results, it is demonstrated that the structures of the complexes and the coordination modes of L1 and L2 are strongly dependent on the metal cations and the anions. The Hg(II) atoms in these complexes have tetrahedral coordination environments, whereas the Cd(II) centers have octahedral coordination geometries when Cl− is used as the anion, affording 3D and 2D coordination networks. The photoluminescence of L1, L2, and the complexes measured in the solid state at room temperature indicated that the emission colors vary from violet to yellow, and the emission intensity varies to a large extent, which can be rationalized by the contribution of a conflicting coordination effect and the heavy atom effect. Self-assembly of N,N,N′,N′-tetra(4-pyridyl)-1,4-phenylenediamine (L1) and N,N-di(2-pyridyl)-N′,N′-di(4-pyridyl)-1,4-phenylenediamine (L2) with MX2 (M = Zn, Cd, and Hg; X = Cl, Br, and I) generated novel supramolecular structures with a rich structural diversity. In the crystal of L1, all pyridyl rings are involved in intermolecular π···π stacking and T-shaped C−H···π interactions to form a two-dimensional (2D) network. [CdL1Cl2]n·nH2O (4), [CdL1I2]n (6), [HgL1Cl2]n (7), [HgL1Br2]n (8), [Cd4(L2)4Cl8]n·2nDMF (13), [CdL2Br2]n (14), [CdL2I2]n (15), and [HgL2Cl2]n·0.5nDMF (16) are coordination polymers. [ABSTRACT FROM AUTHOR]