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Automated Diffraction Tomography for the Structure Elucidation of Twinned, Sub-micrometer Crystals of a Highly Porous, Catalytically Active Bismuth M…

2012

Stepwise Construction of Heterobimetallic Cages by an Extended Molecular Library Approach.

2017

Two novel heterobimetallic complexes, a trigonal-bipyramidal and a cubic one, have been synthesized and characterized using the same C3-symmetric metalloligand, prepared by a simple subcomponent self-assembly strategy. Adopting the molecular library approach, we chose a mononuclear, preorganized iron(II) complex as the metalloligand capable of self-assembly into a trigonal-bipyramidal or a cubic aggregate upon coordination to cis-protected C2-symmetric palladium(II) or unprotected tetravalent palladium(II) ions, respectively. The trigonal-bipyramidal complex was characterized by NMR and UV–vis spectroscopy, electrospray ionization mass spectrometry (ESI-MS), and single-crystal X-ray diffrac…

Fluorescence Quenching in BODIPYs Having Ir‐ and Rh‐Tethered Complexes

2016

The effect of Rh- and Ir-centers on the optical properties of the BODIPY core has been studied. To this end, novel metal complexes tethered to BODIPY have been prepared through an easy and versatile procedure using N-directed C–H activation reactions. The organometallic moiety has a tremendous influence on the emissive properties of the BODIPY fragment. A photoinduced electron transfer (PET) mechanism is suggested to be the main mechanism responsible for the suppression of the BODIPY fluorescence emission in the newly formed dyads. The efficiency of the PET depends on both the distance between the chromophores in the dyad and the nature of the transition metal (Rh vs. Ir).

Bis(2-methylbenzimidazole-κN1)copper(I) dichlorocuprate(I)

2004

By using alternating-current electrochemical synthesis, crystals of the copper(I) ionic compound composed of [Cu(C8H8N2)2]+ and [CuCl2]− ions have been obtained and structurally investigated. Both crystallographically independent Cu atoms lie on centres of inversion and exhibit the less-common coordination number 2. A linear arrangement of the metal atoms includes two N atoms of the different organic moieties in the [Cu(2-methyl­benz­imidazole)2]+ cation and two Cl atoms in the case of the inorganic anion.

A cyanide and hydroxo-bridged nanocage: a new generation of coordination clusters.

2013

International audience; Combining serendipitously-formed hydroxo-clusters, [CoII3(OH)(piv)4(L)]+ (where L = MeCN or Hpiv), with assembling cyanide building block, [FeIII(Tp)(CN)3]−, has led to an unprecedented architecture where polymetallic cobalt clusters and blocked tris-cyanide iron complexes define the apexes of a unique magnetic cubic nanocage.

Synthesis, crystal structures and magnetic properties of picolinate-bridged copper(II) chains

2018

The paper reports the synthesis, crystal structures, and magnetic properties of two copper(II) coordination polymers, Cu2(L1)4 (1) and Cu3(L2)6 (2), based on rigid ethynylene-bridged ditopic ligands containing one picolinate subunit (L1 = 5-(pyridin-3-ylethynyl)picolinate anion; L2 = 5-((4-(methoxycarbonyl)phenyl)ethynyl)picolinate anion). Both 1 and 2 have a chain structure. In 1, the repeating unit in the chain is a doubly bridged picolinate dicopper(II) complex, whereas 2 is built upon trimeric units where the Cu2+ ions are also connected by double picolinate bridges. Both compounds exhibit antiferromagnetic interactions in the solid state. The magnetic properties of 1 and 2 were analyze…

Equipping metallo-supramolecular macrocycles with functional groups: Assemblies of pyridine-substituted urea ligands

2012

A series of di-(m-pyridyl)-urea ligands were prepared and characterized with respect to their conformations by NOESY experiments and crystallography. Methyl substitution in different positions of the pyridine rings provides control over the position of the pyridine N atoms relative to the urea carbonyl group. The ligands were used to self-assemble metallo-supramolecular M(2)L(2) and M(3)L(3) macrocycles which are generated in a finely balanced equilibrium in DMSO and DMF according to DOSY NMR experiments and ESI FTICR mass spectrometry. Again, crystallography was used to characterize the assemblies. Methyl substitution in positions next to the pyridine nitrogen prevents coordination, while …

Cooperative H-bonds, π⋯π and anion⋯π interactions as driving forces in the construction of novel Cu(II) bis(imidazol-2-yl) supramolecular 3D framewor…

2019

Abstract Two new Cu(II) complexes with bis(2-imidazolyl) based ligands, with the formula [Cu(BIM)2(SCN)2]·2H2O (BIM = bis(2-imidazol-2-yl)methane) and [Cu(HBIMAM)2(OH2)2](BF4)4·2H2O (BIMAM = bis(2-imidazol-2-yl)methylaminomethane) have been synthesized and characterized. Both compounds contain mononuclear entities as molecular building blocks (MBBs); neutral [Cu(BIM)2(SCN)2] in compound 1 and cationic [Cu(HBIMAM)2(OH2)2]4+ in compound 2. The coordination around the metal atoms shows a tetragonally-elongated octahedral geometry (CuN4S2 and CuN4O2 chromophores). The Q-band EPR spectra of both compounds are indicative of an essentially d x 2 - y 2 ground state for copper(II) ions. The analysis…

Synthesis, Structural and Spectroscopic Characterization of Cr III , Fe III , Co III , Ni II and Cu II Complexes with an Asymmetric 1,3,4‐Thiadiazole…

2016

The reaction of the new asymmetric 1,3,4-thiadiazole-based ligand 2-[(5-ethylthio-1,3,4-thiadiazol-2-yl)hydrazonomethyl]phenol (H1ETHP) with various third-row transition metal salts resulted in the formation of six new mononuclear complexes [Cr(ETHP)2]ClO4 (1), [Fe(ETHP)2][FeCl4] (2), [Co(ETHP)(ETHP–H)] (3), [Ni(ETHP)(H1ETHP)]Cl (4), [Ni(ETHP)(H1ETHP)](ClO4) (5), [Ni(ETHP)(H1ETHP)]Br (6), and one tetranuclear complex [Cu2Cl3(ETHP)(H1ETHP)]2 (7). H1ETHP and all complexes have been analyzed by single crystal X-ray diffraction. Structural analysis of 1–6 reveals complexes of the [ML2]n+-type (n = 0,1), in which the mono anionic ligand ETHP coordinates in a tridentate NNO fashion via its imine,…

Dicopper(II) pyrazolenophanes: Ligand effects on their structures and magnetic properties

2016

Abstract The use of simple pyrazolate anions and related polychelating acyclic or macrocyclic pyrazolate derivatives as bridging ligands, and occasionally additional blocking ligands, has led to the stereospecific Cu II -mediated self-assembly of both homo- and heteroleptic di-μ-pyrazolatodicopper(II) complexes of the metallacyclophane type, so-called dicopper(II) pyrazolenophanes. Besides their unique molecular conformation features and binding abilities toward both neutral molecules and charged anionic species, which have illustrated the putative role of weak intramolecular π–π stacking, hydrogen bonding, and coordinative interactions in the self-assembling process, dicopper(II) pyrazolen…