A [Mn] Defective Supertetrahedron T3 and Its Dimeric [Mn] Analogue.

The initial use of 2-(pyridin-2-yl)propane-1,3-diol (pypdH) in Mn cluster chemistry has afforded two new mixed-valence polynuclear Mn clusters, namely, [MnΟ(pypd)(hmp)(OCCMe)] () and [MnΟ(N)(pypd){(py)CO}(OCEt)] () (hmp = deprotonated 2-hydroxymethylpyridine; (py)CO = deprotonated gem-diol form of di-2-pyridyl ketone). Compound features a novel [Mn Mn(μ-O)(μ-O)(μ-OR)] structural core resembling a supertetrahedron T3, lacking two apexes, while complex has a [Mn Mn (μ-O)(μ-O)(μ-N)(μ-OR)(μ-OR)] core consisting of two [Mn] subunits related to and thus is a dimeric analogue of . Direct current (dc) magnetic susceptibility studies revealed the presence of dominant antiferromagentic exchange interactions between the Mn ions in complexes and and small ground state spin values for both compounds.

A new family of heterometallic [CuM] (M = Gd, Tb, Dy and Y) clusters derived from the combined use of selected pyridyl poly-alcohol ligands.

The combined use of 2-(2-pyridyl)-1,3-propane-diol (pypdH) and 2-hydroxymethyl-2-(2-pyridyl)-1,3-propane-diol (pyptH) in Cu/4f chemistry has afforded a new family of isostructural [CuM(pypt)(pypdH)(NO)] [M = Gd (1), Tb (2), Dy (3), and Y (4)] complexes. These compounds are based on an unprecedented three-layered symmetric [CuM(μ-OR)] structural core, formed from the connection of the metal ions by bridging alkoxide arms of the organic ligands. Direct current magnetic susceptibility studies for complexes 1-3 revealed the presence of dominant ferromagnetic exchange interactions, suggesting the existence of large spin ground state values.

Solvatomorphism in a series of copper(II) complexes with the 5-phenylimidazole/perchlorate system as ligands.

In the course of an investigation of the supramolecular behaviour of copper(II) complexes with the 5-phenylimidazole/perchlorate ligand system (`blend') remarkable solvatomorphism has been observed. By employing a variety of crystallization solvents (polar protic, polar/non-polar aprotic), a series of 12 crystalline solvatomorphs with the general formula [Cu(ClO)(LH)]·x(solvent) have been obtained [LH = 5-phenylimidazole, x(solvent) = 3.3(HO) (1), 2(methanol) (2), 2(ethanol) (3), 2(1-propanol) (4), 2(2-propanol) (5), 2(2-butanol) (6), 2(dimethylformamide) (7), 2(acetone) (8), 2(tetrahydrofurane) (9), 2(1,4-dioxane) (10), 2(ethyl acetate) (11) and 1(diethyl ether) (12)].

Fine Tuning the Hydrophobicity of a New Three-Dimensional Cu MOF through Single Crystal Coordinating Ligand Exchange Transformations.

The synthesis, characterization, and single-crystal-to-single-crystal (SCSC) exchange reactions of a new 3D Cu MOF based on 5-aminoisophthalic acid (HAIP), [Cu(μ-ΟΗ)(ΑΙΡ)(HΑΙΡ)]·6DMF·HO - ·6DMF·HO, are reported. It exhibits a 3D structure based on two [Cu(μ-OH)] butterfly-like secondary building units, differing in their peripheral ligation, bridged through HAIP/AIP ligands. This compound displays the capability to exchange the coordinating ligand(s) and/or guest solvent molecules through SCSC reactions.

Catalysis of a Diels-Alder Reaction between Azachalcones and Cyclopentadiene by a Recyclable Copper(II)-PEIP Metal-Organic Framework.

Metal-organic frameworks (MOFs) have attracted considerable interest as emerging heterogeneous catalysts for organic transformations of synthetic utility. Herein, a Lewis-acidic MOF, {[Cu(PEIP)(5-NH-BDC)(DMF)]·7DMF}∞, denoted as Cu(ΙΙ)-PEIP, has been synthesized via a one-pot process and deployed as an efficient heterogeneous catalyst for a Diels-Alder cycloaddition. Specifically, the [4 + 2] cycloaddition of 13 substituted azachalcone dienophiles with cyclopentadiene has been investigated.

Interesting chemical and physical features of the products of the reactions between trivalent lanthanoids and a tetradentate Schiff base derived from cyclohexane-1,2-diamine.

The initial use of a tetradentate Schiff base (LH) derived from the 2 : 1 condensation between 2-hydroxyacetophenone and cyclohexane-1,2-diamine in 4f-metal chemistry is described. The 1 : 2 reaction of Ln(NO)·HO (Ln = lanthanoid or yttrium) and LH in MeOH/CHCl has provided access to isostructural complexes [Ln(NO)(L'H)(MeOH)] in moderate to good yields. Surprisingly, the products contain the corresponding Schiff base ligand L'H possessing six aliphatic -CH- groups instead of the -CH-(CH)-CH- unit of the cyclohexane ring, an unusual ring-opening of the latter has occurred.

Heterometallic clusters based on an uncommon asymmetric "V-shaped" [Fe(μ-OR)Ln(μ-OR)Fe] (Ln = Gd, Tb, Dy, Ho) structural core and the investigation of the slow relaxation of the magnetization behaviour of the [FeDy] analogue.

The synthesis, crystal structures, Mössbauer spectra and variable temperature dc and ac magnetic susceptibility studies of a new family of trinuclear heterometallic Fe/Ln complexes, [FeLn(PhCO)((py)CO)((py)C(OMe)O)(NO)Cl] (Ln = Gd (1/Gd), Tb (1/Tb), Dy (1/Dy), and Ho (1/Ho)), where (py)CO and (py)C(OMe)O are the anions of the -diol and hemiketal derivatives of di-2-pyridyl ketone, are reported. Compounds 1/Ln are based on an asymmetric "V-shaped" [Fe(μ-OR)Ln(μ-OR)Fe] structural core formed from the connection of the two terminal Fe centers to the central Ln ion either through one or two alkoxide groups originating from the alkoxide-type bridging ligands. Direct current magnetic susceptibility studies reveal the presence of weak antiferromagnetic interactions between the Fe ions.

NUIG4: A biocompatible pcu metal-organic framework with an exceptional doxorubicin encapsulation capacity.

Metal-organic frameworks (MOFs) are promising multifunctional porous materials for biomedical and environmental applications. Here, we report synthesis and characterization of a new MOF based on the tetrahedral secondary building unit [ZnO(CBAB)] (NUIG4), where CBABH = 4-((4-carboxybenzylidene)amino)benzoic acid. NUIG4 belongs to the family of MOFs with primitive cubic pcu topology, being a rare example with 4-fold interpenetration.

High nuclearity structurally - related Mn supertetrahedral T4 aggregates.

The simultaneous employment of 1,3-propanediol and di-2-pyridyl ketone in Mn carboxylate chemistry has provided access to three new, structurally-related [Mn] and [Mn] clusters. They are based on nanosized supertetrahedal T4 Mn/O structural cores and exhibit slow relaxation of magnetization below 3.5 K.

Influence of ligand positional isomerism on the molecular and supramolecular structures of cobalt(II)-phenylimidazole complexes.

In a study to evaluate the impact of flexible positional isomeric ligands on the coordination geometry and self-assembly process of 3d metal complexes, the synthesis of eight new cobalt(II) complexes with the 2-phenylimidazole (LH) and 5-phenylimidazole (L'H) ligands has been carried out. A variety of parameters/conditions have been probed using the general Co/X/LH or L'H (X = Cl, Br, I, NO, NCS, ClO, SO) reaction system. Interestingly, X-ray analyses reveal two distinct groups of complexes: reactions with LH only lead to tetrahedral or quasi-tetrahedral complexes {i.

Dual Emission in a Ligand and Metal Co-Doped Lanthanide-Organic Framework: Color Tuning and Temperature Dependent Luminescence.

In this study, we report the luminescence color tuning in the lanthanide metal-organic framework (LnMOF) ([La(bpdc)Cl(DMF)] (); bpdc = [1,1'-biphenyl]-4,4'-dicarboxylate, DMF = ,-dimethylformamide) by introducing dual emission properties in a La MOF scaffold through doping with the blue fluorescent 2,2'-diamino-[1,1'-biphenyl]-4,4'-dicarboxylate (dabpdc) and the red emissive Eu. With a careful adjustment of the relative doping levels of the lanthanide ions and bridging ligands, the color of the luminescence was modulated, while at the same time the photophysical characteristics of the two chromophores were retained. In addition, the photophysical properties of the parent MOF () and its doped counterparts with various dabpdc/bpdc and Eu/La ratios and the photoinduced energy transfer pathways that are possible within these materials are discussed.

Spin-Crossover Phenomenon in Microcrystals and Nanoparticles of a [Fe(2-mpz)Ni(CN)] Two-Dimensional Hofmann-Type Polymer: A Detailed Nano-Topographic Study.

The diamagnetic two-dimensional Hofmann-type metal-organic framework [Zn(2-mpz)Ni(CN)] has been successfully synthesized along with its isostructural hysteretic spin-crossover Fe analogue in the form of both bulk microcrystalline powder and nanoparticles. Detailed atomic force microscopy topographic study revealed a nanogrowth relationship between the height and length of the nanoparticle.

Giant Heterometallic [MnNi] and [MnCo] "Loops-of-Loops-and-Supertetrahedra" Molecular Aggregates.

We report the synthesis, crystal structures and magnetic properties of the giant heterometallic [MnNi] (compounds , )/[MnCo] (compound ) "loops-of-loops-and-supertetrahedra" molecular aggregates and of a [MnNi] compound (cation of ) that is structurally related with the cation co-crystallizing with the anion of . In particular, after the initial preparation and characterization of compound [MnNi(μ-O)(μ-OH)(μ-Cl)(OCCH)(py)][MnNi(μ-O)(μ-O)(μ-Cl)Cl(OCCH)(pd)(py)] () we targeted the isolation of (i) both the cationic and the anionic aggregates of in a discrete form and (ii) the Mn/Co analog of [MnNi] aggregate. Our synthetic efforts toward these directions afforded the discrete [MnNi] "loops-of-loops-and-supertetrahedra" aggregate [MnNi(μ-O)(μ-O)(μ-Cl)Cl(OCCH)(pd)(py)(HO)] (), the heterometallic Mn/Co analog [MnCo(μ-O)(μ-O)(μ-Cl)Cl(μ-OCHCH)(OCCH)(pd)(py)] () and the discrete [MnNi] cation [MnNi(μ-O)(μ-OH)(μ-Cl)(OCCH)(py)](ClO)(OH) ().

New metalo-therapeutics of NSAIDs against human breast cancer cells.

The non steroidal anti-inflammatory drugs (NSAID's)-silver(I) metallodrugs of aspirin (aspH), salicylic acid (salH), naproxen (napH) acid or p-hydrobenzoic acid (pHbzaH) and the mitochondriotropic triphenylarsine (tpAs) with the formulae [Ag(asp)(tpAs)] (1), [Ag(salH)(tpAs)] (2), [Ag(nap)(tpAs)] (3) and {[Ag(pHbza)(tpAs)]∙(dmf)} (4) and [Ag(tpAs)(NO)] (5) have been synthesized and characterized by m.p., FT-IR, UV-vis and H NMR, spectroscopic techniques and X-ray crystallography.

Heterometallic MnLn (Ln = Dy, Gd, Tb) Cross-Shaped Clusters and Their Homometallic MnMn Analogues.

The employment of di-2-pyridyl ketone, (py)CO, in heterometallic Mn/4f and homometallic Mn cluster chemistry has yielded six MnLn and two MnMn structurally related clusters, namely, [MnLnO{(py)CO}(NO)(RCO)(HO)](NO) (Ln = Gd, 1, 5; Dy, 2; Tb, 3; R = Et, 1-3; Me, 5), [MnDyO{(py)CO}(NO)(EtCO)(HO)(MeOH)]·0.7MeOH·0.8HO (4·0.

Binding of ligands containing carbonyl and phenol groups to iron(iii): new Fe, Fe and Fe coordination clusters.

The initial use of ligands 2'-hydroxyacetophenone (HL), 2-hydroxybenzophenone (HL) and 2,2'-dihydroxybenzophenone (HL) in iron(iii) chemistry is described. The syntheses and crystal structures are reported for five iron(iii) clusters: [FeO(OMe)(L)(MeOH)](NO)·3MeOH (1·3MeOH), [FeO(OH)(OMe)(L)](ClO)·2HO (2·2HO), [FeO(OMe)Cl(L)(MeOH)] (3), [FeO(OMe)(L)(py)](ClO)·MeOH (4·MeOH), where py = pyridine, and [FeO(OEt)(OCMe)(L)(HL)] (5). The molecular structures of the decanuclear clusters 1, 3 and 4 are organized around a {Fe(μ-O)(μ-OMe)(μ-OMe)} core consisting of ten {FeO} face-sharing defective cubane units.

A hexameric [MnNa] wheel based on [MnO] sub-units.

A novel hexameric [MnNa] wheel-like aggregate consisting of [MnO] triangles is reported. It is the second highest nuclearity oxime-based Mn cluster, the largest member of the recently-developed family of molecular oligomers based on [MnO] triangles, and the only one with a wheel-like metal topology.

Nimesulide Silver Metallodrugs, Containing the Mitochondriotropic, Triaryl Derivatives of Pnictogen; Anticancer Activity against Human Breast Cancer Cells.

Novel silver(I) metallo-drugs of the nonsteroidal anti-inflammatory drug nimesulide (nim) and the mitochondriotropic triaryl derivatives of pnictogen ligands (tpE, E = P (tpp, tptp, or totp), As (tpAs), Sb (tpSb)) with the formulas {[Ag(nim) (tpp)2]DMF} (1), [Ag(nim) (tptp)2] (2), [Ag(nim) (totp)] (3), [Ag(nim) (tpAs)2] (4), and [Ag(nim) (tpSb)3] (5) ((tpp = triphenyphosphine, tptp = tri(p-tolyl)phosphine, totp = tri(o-tolyl)phosphine, tpAs = triphenylarsine, tpSb = triphenylantimony, and DMF = dimethylformamide) were synthesized and characterized by melting point, vibrational spectroscopy (mid-Fourier transform IR), (1)H NMR, UV-visible spectroscopic techniques, and X-ray crystallography. The in vitro cytotoxic activity of 1-5 against human breast adenocarcinoma cancer cell lines: MCF-7 (estrogen receptor (ER) positive) and MDA-MB-231 (ER negative) was determined. The genotoxicity on normal human fetal lung fibroblast cells (MRC-5) caused by 1-5 was evaluated by fluorescence microscopy.

Molecules at the Quantum-Classical Nanoparticle Interface: Giant Mn70 Single-Molecule Magnets of ∼4 nm Diameter.

Two Mn70 torus-like molecules have been obtained from the alcoholysis in EtOH and 2-ClC2H4OH of [Mn12O12(O2CMe)16(H2O)4]·4H2O·2MeCO2H (1) in the presence of NBu(n)4MnO4 and an excess of MeCO2H. The reaction in EtOH afforded [Mn70O60(O2CMe)70(OEt)20(EtOH)16(H2O)22] (2), whereas the reaction in ClC2H4OH gave [Mn70O60(O2CMe)70(OC2H4Cl)20(ClC2H4OH)18(H2O)22] (3). The complexes are nearly isostructural, each possessing a Mn70 torus structure consisting of alternating near-linear [Mn3(μ3-O)4] and cubic [Mn4(μ3-O)2(μ3-OR)2] (R = OEt, 2; R = OC2H4Cl, 3) subunits, linked together via syn,syn-μ-bridging MeCO2(-) and μ3-bridging O(2-) groups.

Introducing Dimensionality to the Archetypical Mn12 Single-Molecule Magnet: a Family of [Mn12]n Chains.

The [Mn12O12(O2CR)16(L4)] family (R = various; L = terminal ligand) of clusters holds a special place in molecular magnetism; they are the most well-studied single-molecule magnets (SMMs). Targeted linkage of these SMMs has now been achieved for the first time. The resulting chain structures have been confirmed crystallographically, and the magnetic properties, up to 1.

Filling the gap between the quantum and classical worlds of nanoscale magnetism: giant molecular aggregates based on paramagnetic 3d metal ions.

In this review, aspects of the syntheses, structures and magnetic properties of giant 3d and 3d/4f paramagnetic metal clusters in moderate oxidation states are discussed. The term "giant clusters" is used herein to denote metal clusters with nuclearity of 30 or greater. Many synthetic strategies towards such species have been developed and are discussed in this paper.

Interesting copper(ii)-assisted transformations of 2-acetylpyridine and 2-benzoylpyridine.

The reactions of various copper(ii) sources with 2-acetylpyridine, (py)(me)CO, and 2-benzoylpyridine, (py)(ph)CO, under strongly basic conditions have been studied and novel ligand transformations have been discovered. Reaction of Cu(ClO4)2·6H2O and (py)(me)CO in the presence of NBu4(n)OMe (1 : 1 : 1) in CHCl3 gave a mixture of [Cu2Cl2(HLA)2](ClO4)2 (1) and [Cu2Cl2(LB)2(ClO4)2] (2), where HLA is 3-hydroxy-1,3-di(pyridin-2-yl)-butane-1-one and LB is the zwitterionic-type ligand 3-hydroxy-1-methyl-3-(pyridin-2-yl)-3H-indolizin-4-ium. The ligand HLA is formed through an aldol reaction-type mechanism, while the formation of LB takes place via an intramolecular nucleophilic attack of the remote 2-pyridyl nitrogen atom on the positive carbonyl carbon of HLA, after the transformation of the latter through deprotonation and dehydration.

Magnetic "Molecular Oligomers" Based on Decametallic Supertetrahedra: A Giant Mn49 Cuboctahedron and its Mn25Na4 Fragment.

Two nanosized Mn49 and Mn25Na4 clusters based on analogues of the high-spin (S=22) [Mn(III)6Mn(II)4(μ4-O)4](18+) supertetrahedral core are reported. Mn49 and Mn25Na4 complexes consist of eight and four decametallic supertetrahedral subunits, respectively, display high virtual symmetry (O(h)), and are unique examples of clusters based on a large number of tightly linked high nuclearity magnetic units. The complexes also have large spin ground-state values (Mn49: S=61/2; Mn25Na4: S=51/2) with the Mn49  cluster displaying single-molecule magnet (SMM) behavior and being the second largest reported homometallic SMM.

A single-chain magnet based on linear [Mn(III)2Mn(II)] units.

The synthesis, structural characterization and magnetic properties of a 1D coordination polymer based on a linear mixed valent [Mn(III)2Mn(II)] repeating unit are described. It displays single-chain magnet (SCM) behaviour with an energy barrier of ∼38 K and represents the first example of a mixed valent Mn-carboxylate SCM with a linear architecture.

Discrete and encapsulated molecular grids: homometallic Mn15 and heterometallic Mn24Ni2 aggregates.

Two molecular grid-like clusters are reported, one is a discrete [3 × 5] grid and the other a [3 × 4] grid within a Mn12Ni2 loop. Both Mn24Ni2 and Mn15 aggregates display novel and aesthetically pleasing structures with the former one being among the highest nuclearity heterometallic MnxMy clusters (M = any transition metal ion).