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The first neo-confused hexaphyrin(1.1.1.1.1.0) was synthesized by oxidative ring closure of a hexapyrrane bearing two terminal 'confused' pyrroles. The new compound displays a folded conformation with a short interpyrrolic C⋅⋅⋅N distance of 3.102 Å, and thus it readily underwent ring fusion to afford a neo-fused hexaphyrin with an unprecedented 5,5,5,7-tetracyclic ring structure. Furthermore, coordination of CuII triggered a ring opening/contracting reaction to afford a CuII complex of an N-linked pentaphyrin derivative. The roles of reactive NC bonds in the porphyrinoid macrocycles were demonstrated. [ABSTRACT FROM AUTHOR]

Complexes of new Schiff base ligands generated in situ from the reaction of 1-aminoglycerol, aldehydes, and metal ions are reported. [Cu4(HL1)4] ( 1) and [Ni4O(HL1)3(H2O)3)] ⋅6 H2O ⋅DMF ⋅DMSO ( 2) have M4O4 cubane cores, with the L/M molar ratios of 4:4 and 3:4, respectively. [MnIII3MnIINaOCl4(HL1)3] ⋅3 MeCN ( 3) has a unique pentanuclear trigonal propeller-shaped MnIII3MnIINa core structure, and the coordination assemblies are linked by hydrogen bonds to afford a 3D channel structure. [Cu2(HL2)2] ( 4) has a bis(μ2-alkoxo)-bridged Cu2O2 core, with the binuclear species linked by hydrogen bonds to afford a 1D double-chain. [Ni7(OH)2(OCH3)4(H2L3)2(MeOH)2(H2O)2]- (ClO4)2 ⋅10 H2O ( 5) has a heptanuclear structure containing heptadentate di-Schiff base ligands, with the nickel(II) ions bridged by phenoxo, alkoxo, hydroxo, and methoxo groups to afford a very rare face-sharing hexadruple defective cubane core with a Ni@Ni6 arrangement. The lattice water molecules are linked by hydrogen bonds to form helical chains, which are further hydrogen-bonded to the coordination moieties to afford a 2D network. Variable temperature magnetic susceptibility measurements and nonlinear data-fitting revealed that the '2+4' type of cubane complex 1 shows medium intradimeric ferromagnetic interactions and weak interdimeric ferromagnetic interactions. For complexes 2 and 5, coexistent ferro- and antiferromagnetic couplings afford a non-zero spin ground state. However, compound 3 shows antiferromagnetic interactions between MnIII and MnII, and ferromagnetic interactions between the MnIII centers, resulting in a global antiferromagnetic behavior. In conclusion, the reaction of 1-aminoglycerol with aldehydes and metal salts afforded polynuclear complexes with a rich structural diversity and remarkable magnetic behavior. [ABSTRACT FROM AUTHOR]

The porphyrin macrocycle is one of the most frequently investigated functional molecular entities and can be incorporated into advanced functional nanomaterials upon formation of organized nanostructures. Thus, study of the science and technology of porphyrin assemblies has attracted many organic, biological and supramolecular chemists. A wide variety of nanostructures can be obtained by supramolecular self-assembly because the porphyrin moiety is amenable to chemical modifications through thoughtful synthetic design and moderate preparative effort. Some recent developments in porphyrin assembly, obtained through various supramolecular approaches, are briefly summarized. Topics described in this review are classified into four categories: (i) non-specific assemblies; (ii) specific assemblies; (iii) assemblies in organized films; (iv) molecular-level arrangement. We present examples in the order of structural precision of assemblies. [ABSTRACT FROM AUTHOR]

Two novel Cu(II) complexes, [Cu(H2tpda)(acac)](ClO4)0.5Cl0.5 · H2O, [Cu(H2tpda)(NO3)]ClO4 (2) (H2tpda = tripyridyldiamine) have been synthesized, and characterized by X-ray analyses, elemental analyses, IR, UV and ESR spectra. Single crystal X-ray diffraction revealed that the Cu atom in complex 1 is coordinated to three N atoms from H2tpda and two oxygen atoms from acac with an approximately trigonal bipyramidal geometry. The molecules are assembled through intermolecular hydrogen bonds and π-π stacking, affording a two dimensional network. In complex 2, the Cu atom is coordinated with three N atoms from H2tpda and two oxygen atoms from [image omitted] in addition to a weak coordination with one oxygen from [image omitted], resulting in an irregular octahedral environment, and the molecules are also connected by intermolecular hydrogen bonding and π-π stacking, affording a one dimensional structure. [ABSTRACT FROM AUTHOR]

Complex [Cu(2,2′-bpy)(H2L1)](ClO4)2 (1) has been self-assembled by the complexation of a potentially flexible tetradenate ligand 1,2-bis((2-hydroxyetheyl)amino)ethane (H2L1) and a chelating rigid ligand 2,2′-bipyridine (bpy) with Cu(II). Crystal analyses reveal that H2L1 acts as a tridenate ligand by the coordination of one alkoxyl O atom and two amino N atoms. Copper(II) coordinates additionally with the two N atoms of bipyridine, giving a distorted square pyramidal geometry. Each complex molecule is connected with four surrounding ones by hydrogen bonds along the ac plane, leading to 2D sheets constituted with 7.874×10.891 A˚ metallomacrocyclic rectangles. Each vertex of the rectangle is occupied by a copper atom. The four sides are comprised of multiple hydrogen bonds. Electronic spectra of complex 1 showed a band maximum at 661 nm; the EPR spectra of 1 in frozen DMF at 100 K showed an axial spectrum with four hyperfine peaks in the g∥ region, and g∥>g⊥, consistent with a distorted square pyramidal copper(II) coordination geometry. [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]

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]

In the past decades, porphyrin analogues have attracted increasing attention in light of their unique properties and potential applications in various areas. In this work, novel nonconjugated thiophene-embedded N -confused homoporphyrins 1 and 2 as well as a fully-conjugated N -fused homoporphyrin 3 have been prepared through acid-catalyzed condensation reactions followed by oxidation. Both 1 and 2 comprise two meso-sp3-carbon atoms. However, they are insensitive to the air or common oxidants. Single crystal X-ray diffraction analysis reveals that 2 adopts a highly distorted boat-like conformation, with the NH moieties of two pyrrolic units pointing outwards and an O atom attached to the α position of the N -confused pyrrole unit. As a result, hydrogen-bonded dimers are formed through the intermolecular hydrogen bonds between the lactam-like moieties. In contrast to the highly distorted structure of 2 , N -fused homoporphyrin 3 contains a unique 5,5,5–tricyclic fused ring, and thus demonstrates a relatively coplanar conformation except one inverted pyrrole unit. Because of the different structural characters, 3 exhibits F− binding behavior distinct from that of 1 and 2. [Display omitted] • Facile syntheses of stable thiophene-embedded N -confused homoporphyrins. • Partially and completely conjugated homoporphyrins modulated by oxidants. • Tunable fluoride binding behavior based on the different structures. [ABSTRACT FROM AUTHOR]