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Two complementary examples of porphyrin nanoarchitectonicsare presented. The fabrication of binary molecular monolayers usingtwo different porphyrin molecules, tetrakis(3,5-di-t-butyl-4-hydroxyphenyl)porphyrin (1) and tetrakis(4-pyridyl)porphyrin (2), by depositionin ultrahigh vacuum was demonstrated. Two unusual heteromolecularmonolayer structures were observed, with one exhibiting good separationof 1molecules within the monolayer. Also, a syntheticnanoarchitectonic approach was used to prepare self-assembled molecularnanowires at a mica substrate. The nanowires could be observed togrow using atomic force microscopy (AFM), and the network structuresof the nanowires could be influenced by manipulation using the AFMprobe tip. [ABSTRACT FROM AUTHOR]

Sensing of metal ions and anions is of great importance because of their widespread distribution in environmental systems and biological processes. Colorimetric and fluorescent chemosensors based on organic molecular species have been demonstrated to be effective for the detection of various ions and possess the significant advantages of low cost, high sensitivity, and convenient implementation. Of the available classes of organic molecules, porphyrin analogues possess inherently many advantageous features, making them suitable for the design of ion chemosensors, with the targeted sensing behavior achieved and easily modulated based on their following characteristics: (1) NH moieties properly disposed for binding of anions through cooperative hydrogen-bonding interactions; (2) multiple pyrrolic N atoms or other heteroatoms for selectively chelating metal ions; (3) variability of macrocycle size and peripheral substitution for modulation of ion selectivity and sensitivity; and (4) tunable near-infrared emission and good biocompatibility. In this Review, design strategies, sensing mechanisms, and sensing performance of ion chemosensors based on porphyrin analogues are described by use of extensive examples. Ion chemosensors based on normal porphyrins and linear oligopyrroles are also briefly described. This Review provides valuable information for researchers of related areas and thus may inspire the development of more practical and effective approaches for designing high-performance ion chemosensors based on porphyrin analogues and other relevant compounds. [ABSTRACT FROM AUTHOR]

A C6F5-substituted hexapyrrane (1) wassynthesized in one step. Oxidative cyclization of 1withDDQ afforded a phlorin–dipyrrin conjugate (2),and subsequent FeCl3-assisted oxidative cleavage of 2afforded a terminally di-α-methoxy substituted hexapyrrin(3). On the other hand, oxidation of 1withFeCl3afforded 3, a hexapyrrinone Fe3+complex (4), and a hexaphyrin (1,1,1,1,1,0) (5). These results indicate that the oxidation of hexapyrranesmay be developed as an effective approach for the syntheses of novellinear and macrocyclic hexapyrroles. [ABSTRACT FROM AUTHOR]

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]

In situ formation of ligands is an efficient approachto synthesizingnovel complexes with unique coordinating moieties. Oxazolidines andoxazinanes are 1,3-N,O-containing five-membered and six-membered heterocycles,respectively. Metal complexes of ligands derived from these two heterocyclesare rather rare. In this work, we designed and synthesized a novelmultihydoxy ligand, 2-((2,3-dihydroxypropylamino)methyl)phenol (H3L1). It contains both aminoethanol and aminopropanolunits, which may be employed to react with aldehydes to afford oxazolidinesand oxazinanes, respectively. Thus, H3L1wasreacted with metal salts in the absence or presence of aldehydes toafford complexes [Cu(HL1)]2(1),[CuL2]4·4CH3OH (2) [Zn5Na2(L3)4(DMSO)2.65(DMF)1.35]·DMF (3), and [Ni(HL4)]2(4). Complex 1is a dialkoxo-bridged binuclear Cu(II) complex. The coordinationmoieties are linked by intermolecular C–H···Ohydrogen bonds to afford a 1D double-chain supramolecular structure.Interestingly, in complexes 2–4,H3L1has been reacted with formaldehyde, salicylaldehyde,and 2,6-diformyl-4-cresol to afford novel ligands H2L2, H3L3, and H3L4, respectively. The combination of in situ formed oxazinane or oxazolidinerings with appended alkoxyl and phenol functionalities in these ligandshas been demonstrated to form a rich diversity of coordination structures.Thus, 2is a tetranuclear Cu(II) complex with a face-sharingdouble defective cubane core structure. In this complex, (L2)2–ligands coordinate in two different bridgingmodes with the Harris notations of 3.1121221311and 3.1131231111, respectively. Complex 3has an interestingheptanuclear Zn5Na2core structure. A centralZn(II) is coordinated with four alkoxo O atoms from four (L3)3–ligands. Each of the O atom further bridgesanother Zn(II) atom, resulting in a Zn5moiety, which isthen connected to two Na phenoxo O bridges, finallyaffording the Zn5Na2core. The bridging modeof (L3)3–can be designated as 4.21221311312411.And Complex 4is a binuclear Ni(II) complex containingdi-μ2-phenoxo bridges. The coordination moietiesare linked by intermolecular C–H···π,C–H···O, and π···πinteractions to afford a two-dimensional supramolecular network. Theseresults indicate that the combination of in situ formed oxazinaneand oxazolidine rings with appended phenol and alkoxyl functionalitiesis an efficient approach to developing novel ligands and complexeswith a rich structural diversity. Variable temperature magnetic datameasurements revealed that medium antiferromagnetic interaction existsbetween the Cu(II) centers in complex 1with a −2Jvalue of 278 cm–1. And in complex 4, weak antiferromagnetic coupling occurs between the Ni(II)centers, with a −2Jvalue of 9.36 cm–1. [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]