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Voigt J, Baljozović M, Martin K, Wäckerlin C, Avarvari N, Ernst KH. An aperiodic chiral tiling by topological molecular self-assembly. Nat Commun 2025; 16:83. [PMID: 39747821 PMCID: PMC11696205 DOI: 10.1038/s41467-024-55405-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2024] [Accepted: 12/11/2024] [Indexed: 01/04/2025] Open
Abstract
Studying the self-assembly of chiral molecules in two dimensions offers insights into the fundamentals of crystallization. Using scanning tunneling microscopy, we examine an uncommon aggregation of polyaromatic chiral molecules on a silver surface. Dense packing is achieved through a chiral triangular tiling of triads, with N and N ± 1 molecules at the edges. The triangles feature a random distribution of mirror-isomers, with a significant excess of one isomer. Chirality at the domain boundaries causes a lateral shift, producing three distinct topological defects where six triangles converge. These defects partially contribute to the formation of supramolecular spirals. The observation of different equal-density arrangements suggests that entropy maximization must play a crucial role. Despite the potential for regular patterns, all observed tiling is aperiodic. Differences from previously reported aperiodic molecular assemblies, such as Penrose tiling, are discussed. Our findings demonstrate that two-dimensional molecular self-assembly can be governed by topological constraints, leading to aperiodic tiling induced by intermolecular forces.
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Manna F, Oggianu M, Mameli V, Lai S, Simbula A, Quochi F, Avarvari N, Mercuri ML. Thiophenyl Anilato-Based NIR-Emitting Lanthanide (Ln III = Er, Yb) Dinuclear Complexes. Molecules 2024; 29:5804. [PMID: 39683961 DOI: 10.3390/molecules29235804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2024] [Revised: 11/23/2024] [Accepted: 12/05/2024] [Indexed: 12/18/2024] Open
Abstract
By combining ErIII and YbIII ions with 3,6-dithiophene-anilate (Th2An) and scorpionate hydrotris(pyrazol-1-yl)borate (HBpz3-) ligands new luminescent dinuclear complexes are obtained. The two materials formulated as [((HB(pz)3)2Yb)2(μ-th2An)]·4DCM·1.3H2O 1Yb and [((HB(pz)3)2Er)2(μ-th2An)]·4DCM·1.8H2O 1Er, respectively, have been structurally characterized by SC-XRD and PXRD studies. This study presents a comprehensive investigation of the photophysical properties of the Th2An ligand for the first time. Our findings reveal the crucial role of the thiophene anilate as an effective optical antenna, which sensitizes near-infrared (NIR)-emitting lanthanide ions, specifically ErIII and YbIII. The significant impact of vibrational quenching on the LnIII NIR emission efficiency has been also highlighted.
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Ferrari C, Bogdan A, Pop F, Curto C, Carella A, Rossella F, Avarvari N, Fontanesi C. Enantio-Recognition and Charge Transfer Complex Formation Involving Tetrathiafulvalene-Appended Chiral 1,2-Cyclohexane-Diamine: An Integrated Experimental and Theoretical Study. Chirality 2024; 36:e70009. [PMID: 39696729 DOI: 10.1002/chir.70009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2024] [Revised: 11/29/2024] [Accepted: 11/29/2024] [Indexed: 12/20/2024]
Abstract
In this work, we exploit the electronic features of tetrathiafulvalene (TTF) as a backbone in synthesizing chiral derivatives. The aim is to make use of TTF's well-known and unique redox and semiconducting properties in the fields of enantio-selective recognition and chiral charge transfer (CT) complex preparation, with the ultimate objective of obtaining devices with various potential applications, ranging from plasmonics to quantum computing. In particular, both cyclohexane-bis (TTF-amide)-based enantiomers 1-(S,S) and 1-(R,R), stable under an oxidation regime, have been selected, and under these conditions, the electrochemical enantiospecific response of the four possible systems, coming from the combination with L- and D-tartaric acid, respectively, was tested. The 1:tartaric acid adducts show lower oxidation potentials than the pristine 1, together with clear enantio-discrimination demonstrated by sizeable potential differences in the range of 29-46 mV between the diastereomeric adducts. Because the oxidation potential of 1 suggests the possibility of the formation of CT complexes, impedance and FT-IR spectra were recorded to confirm this hypothesis in the case of the CT complex 1:I2. The experimental results obtained through the FT-IR analysis were also compared with the theoretical results deriving from the DFT-based calculations.
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Manna F, Oggianu M, Auban-Senzier P, Novitchi G, Canadell E, Mercuri ML, Avarvari N. A highly conducting tetrathiafulvalene-tetracarboxylate based dysprosium(iii) 2D metal-organic framework with single molecule magnet behaviour. Chem Sci 2024; 15:19247-19263. [PMID: 39574533 PMCID: PMC11576575 DOI: 10.1039/d4sc05763e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2024] [Accepted: 10/29/2024] [Indexed: 11/24/2024] Open
Abstract
The synthesis and whole characterization by a multitechnique approach of an unprecedented dysprosium(iii) 2D metal organic framework (MOF), involving the redox-active tetrathiafulvalene (TTF)-based linker TTF-tetracarboxylate (TTF-TC), are herein reported. The single-crystal X-ray structure, formulated as [Dy6(TTF-TC)5(H2O)22]·21H2O (1), reveals a complex 2D topology, with hexanuclear Dy6 clusters as secondary building units (SBUs) interconnected by five linkers, stacked almost parallel in each layer and eclipsed along the [111] direction, leading to the formation of 1D channels filled by water molecules. The mixed valence of the TTF units is confirmed by both bond distance analysis, Raman microscopy and diffuse reflectance spectroscopy, and further supported by band structure calculations, which also predict activated conductivity for this material. Thanks to efficient TTF stacking and partial oxidation, 1 shows semiconducting behavior, with, however, a record conductivity value of 1 mS cm-1 at room temperature, when compared to the previously reported TTF-based MOFs. Furthermore, temperature and magnetic field dependent ac (alternative current) magnetic susceptibility measurements demonstrate field induced slow relaxation of magnetization, accounting for two independent relaxation processes, with an energy barrier (U eff/K) of around 12 K, typical for dysprosium carboxylate complexes. The herein reported 2D Dy-MOF provides a valuable master plan for coexistence of conducting π-TTF stacks and highly anisotropic DyIII SMM properties.
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Oggianu M, Bertolotti F, Manna F, Congiu F, Cappai A, Melis C, Concas G, Avarvari N, Masciocchi N, Mercuri ML. Slow magnetic relaxation in a heteroleptic anilate-based Dy III metal-organic framework. Dalton Trans 2024; 53:14265-14271. [PMID: 39132810 DOI: 10.1039/d4dt01979b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Novel heteroleptic anilate-based lanthanide MOFs (LnIII = Tb, Dy, Ho) have been obtained under hydrothermal conditions by the ancillary ligand synthetic strategy. These structurally isomorphous species contain octacoordinated LnIII ions with coordination polyhedra approaching an ideal D2d symmetry, best described by a distorted biaugmented trigonal prismatic C2v geometry. In the whole series, only the Dy-MOF exhibits SMM behaviour.
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Martin K, Aharon T, Mastropasqua Talamo M, Hauser A, Bürgi T, Vanthuyne N, Caricato M, Avarvari N. Helicene Appended Benzothiadiazoles as Chiral Emitters. Chemistry 2024; 30:e202401413. [PMID: 38770893 DOI: 10.1002/chem.202401413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 05/20/2024] [Accepted: 05/21/2024] [Indexed: 05/22/2024]
Abstract
A homologous series of 4,7-bis(aryl) substituted benzothiadiazole (BTD) compounds, containing the helicenic derivatives bis([4]helicene), bis([5]helicene) and bis([6]helicene), have been prepared upon a double Suzuki coupling between 3,6-bis(pinacolyl-borane)-BTD and the corresponding bromo-aryl precursors. The single crystal X-ray structure of the bis([4]helicene) compound shows the existence of both helicities (M) and (P) on the same molecule. All the compounds of the series are highly emissive in solution, with quantum yields of the emission ranging from 50 to 91 %. The enantiopure compounds (M,M) and (P,P) for the BTD-bis([6]helicene) have been prepared from the corresponding enantiopure 2-bromo-[6]helicene precursors. Their chiroptical properties have been investigated in correlation with density functional theory (DFT) calculations, which allowed to confidently assign the absolute configuration of the helicene arms and to characterize the different electronic transitions, including the low energy charge transfer excitation from helicenes to BTD. The enantiomerically pure fluorophores (M,M)- and (P,P)-BTD-bis([6]helicene), which exist in solution as two main conformers, according to the DFT calculations, show CPL activity in solution, with glum factors of ≈1.7×10-3 at λem=525 nm, and also in the solid state, with glum factors of ≈1.2×10-3 in spite of the strong decrease of the quantum efficiency.
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Domingos SR, Tikhonov DS, Steber AL, Eschenbach P, Gruet S, Hrodmarsson HR, Martin K, Garcia GA, Nahon L, Neugebauer J, Avarvari N, Schnell M. Evolution of the ionisation energy with the stepwise growth of chiral clusters of [4]helicene. Nat Commun 2024; 15:4928. [PMID: 38858352 PMCID: PMC11164862 DOI: 10.1038/s41467-024-48778-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 05/13/2024] [Indexed: 06/12/2024] Open
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are widely established as ubiquitous in the interstellar medium (ISM), but considering their prevalence in harsh vacuum environments, the role of ionisation in the formation of PAH clusters is poorly understood, particularly if a chirality-dependent aggregation route is considered. Here we report on photoelectron spectroscopy experiments on [4]helicene clusters performed with a vacuum ultraviolet synchrotron beamline. Aggregates (up to the heptamer) of [4]helicene, the smallest PAH with helical chirality, were produced and investigated with a combined experimental and theoretical approach using several state-of-the-art quantum-chemical methodologies. The ionisation onsets are extracted for each cluster size from the mass-selected photoelectron spectra and compared with calculations of vertical ionisation energies. We explore the complex aggregation topologies emerging from the multitude of isomers formed through clustering of P and M, the two enantiomers of [4]helicene. The very satisfactory benchmarking between experimental ionisation onsets vs. predicted ionisation energies allows the identification of theoretically predicted potential aggregation motifs and corresponding energetic ordering of chiral clusters. Our structural models suggest that a homochiral aggregation route is energetically favoured over heterochiral arrangements with increasing cluster size, hinting at potential symmetry breaking in PAH cluster formation at the scale of small grains.
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Bogdan A, Moraru IT, Vanthuyne N, Auban-Senzier P, Grosu I, Avarvari N, Pop F. Chiral Spiro-Tetrathiafulvalenes: Synthesis, Chiroptical Properties, Conformational Issues and Charge Transfer Complexes. Chemistry 2024; 30:e202400564. [PMID: 38525656 DOI: 10.1002/chem.202400564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 03/14/2024] [Accepted: 03/18/2024] [Indexed: 03/26/2024]
Abstract
Within this work we have investigated spiro-based tetrathiafulvalenes (TTFs) obtained as mixtures of stereoisomers from racemic spiro[5.5]undeca-1,8-dien-3-one. Compared to previously described spiro-TTFs, enantiomeric and diastereoisomeric forms have been here separated by chiral HPLC and fully characterized both experimentally and theoretically. The two types of spiro-based chiral derivatives contain either one (2) or three (1) chiral centres out of each one is spiro-type. Experimental CD, supported by TD-DFT calculations, shows differences in the optical activity between the 1 and 2 and their intermediates. The low optical activity of 2 and 3 (spiro alone chirality) was attributed to the presence of two conformers in the solution (ax and eq) of opposite Cotton effect whereas in the case of 1 and 5 (spiro and stereogenic centres) the spiro chirality seems to be responsible of the Cotton effect in the high energy region whereas the R and S chirality in the low energy region. Racemic and enantiopure forms have been successfully used for the synthesis of charge transfer complexes with tetracyanoquinodimethane (TCNQ) based acceptors.
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Plyuta N, Barra AL, Novitchi G, Avarvari N. Six-coordinated nickel(II) complexes with benzothiadiazole Schiff-base ligands: synthesis, crystal structure, magnetic and HFEPR study. Dalton Trans 2024; 53:8835-8842. [PMID: 38716673 DOI: 10.1039/d4dt01143k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Two new nickel(II) complexes, namely Ni(L1)2 (1) and Ni(L2)2·CH2Cl2(2) were obtained by reacting nickel(II) acetate tetrahydrate with the benzothiadiazole Schiff base ligands HL1 = 2-[4-(2,1,3-benzothiadiazole)imino]methyl-phenol or HL2 = 2-[(2,1,3-benzothiadiazol-4-ylimino)methyl]-6-methoxyphenol in the presence of Et3N. The tridentate NNO chelate ligands induce a distorted octahedral environment around the nickel(II) ions. Single crystal X-ray diffraction analysis reveals elongated Ni-N bonds with the nitrogen atom of the benzothiadiazole ring in both complexes. Intermolecular hydrogen bonds and π-π stacking interactions create two-dimensional and three-dimensional supramolecular arrays, respectively, for complexes 1 and 2. Magnetic susceptibility and high-field electron paramagnetic resonance measurements show the presence of significant magnetic anisotropy, with an axial distortion parameter D of -8--10 cm-1.
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Manna F, Oggianu M, Galán-Mascarós JR, Pop F, Le Guennic B, Mercuri ML, Avarvari N. Tuning the slow magnetic relaxation with the substituents in anilate bridged bis(dysprosium) complexes. Dalton Trans 2024; 53:8369-8381. [PMID: 38669068 DOI: 10.1039/d4dt00175c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2024]
Abstract
Dinuclear lanthanide complexes [((HB(pz)3)2Dy)2(μ-Th2An)] (1Dy) and [((HB(pz)3)2Dy)2(μ-ClCNAn)] (2Dy), based on the hydrotris(pyrazol-1-yl)borate (HBpz3-) scorpionate capping ligand and anilate (An2-) bridging linkers, namely homosubstituted dithiophene- and heterosubstituted chlorocyanoanilate, bearing electron-donating and withdrawing substituents at the 3,6-positions of the benzoquinone core, are reported. 1Dy shows an octacoordinated {N6O2} DyIII ion within a D4h distorted square antiprismatic coordination, an ideal geometry for Single-Molecule Magnet (SMM) behavior, given its oblate nature, whereas in 2Dy the octacoordinated DyIII ion adopts a D2d triangular dodecahedron geometry, while maintaining the same {N6O2} coordination sphere. Both complexes show field-induced single molecule magnet (SMM) behaviour, with tuning of the slow magnetic relaxation as a function of the nature of the substituents at the 3,6-positions of the anilate moiety. A comparison of the Arrhenius fitting parameters for 1Dy and 2Dy supports the hypothesis that square antiprismatic DyIII complexes, as 1Dy, exhibit higher energy barriers. This interpretation is supported by ab initio calculations that also shed light on the crucial role of intermolecular dipolar interactions.
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Vensaus P, Liang Y, Zigon N, Avarvari N, Mujica V, Soler-Illia GJAA, Lingenfelder M. Hybrid mesoporous electrodes evidence CISS effect on water oxidation. J Chem Phys 2024; 160:111103. [PMID: 38511663 DOI: 10.1063/5.0199339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/05/2024] [Indexed: 03/22/2024] Open
Abstract
Controlling product selectivity is essential for improving the efficiency of multi-product reactions. Electrochemical water oxidation is a reaction of main importance in different applications, e.g., renewable energy schemes and environmental protection, where H2O2 and O2 are the two principal products. In this Communication, the product selectivity of electrochemical water oxidation was controlled by making use of the chiral induced spin selectivity (CISS) effect at mesoporous-TiO2 on the molecule-modified Au substrate. Our results show a decrease in H2O2 formation when using chiral hetero-helicene molecules adsorbed on the Au substrate. We propose a mechanism for this kinetic effect based on the onset of CISS-induced spin polarization on the Au-helicene chiral interface. We also present a new tunable substrate to investigate the CISS mechanism.
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Zigon N, Solano F, Auban-Senzier P, Grolleau S, Devic T, Zolotarev PN, Proserpio DM, Barszcz B, Olejniczak I, Avarvari N. A redox active rod coordination polymer from tetrakis(4-carboxylic acid biphenyl)tetrathiafulvalene. Dalton Trans 2024; 53:4805-4813. [PMID: 38372362 DOI: 10.1039/d3dt04280d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
An enlarged version of the ubiquitous tetrathiafulvalene-tetrabenzoic acid is described, with 4,4'-biphenyl moieties as spacers between the coordination moieties and the electroactive core. The obtained rectangular ligand has a 14 × 22 Å2 size and is combined with Zn(II) under solvothermal conditions to yield a coordination polymer endowed with large cavities of ca. 15 × 11 Å2/10 × 10 Å2. The topology of the material is discussed in detail using the Points of Extension and Metals (PE&M) or the Straight-rod (STR) representation, and the sqc1121 or tfo topological type of the structure is observed, respectively. Its stability towards solvent removal and electrical properties are discussed. The material does not present any permanent porosity upon desolvation according to nitrogen sorption measurements at 77 K. Nevertheless, a significant increase in conductivity is observed on compressed pellets of the material upon post-synthetic oxidation with iodine. Raman spectroscopy combined with density functional theory (DFT) calculations has been used to characterize the oxidation state of tetrakis(4-carboxylic acid biphenyl)tetrathiafulvalene for coordination polymers.
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Stefani A, Bogdan A, Pop F, Tassinari F, Pasquali L, Fontanesi C, Avarvari N. Spin-dependent electrochemistry and electrochemical enantioselective recognition with chiral methylated bis(ethylenedithio)-tetrathiafulvalenes. J Chem Phys 2023; 159:204706. [PMID: 38014785 DOI: 10.1063/5.0171831] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 11/02/2023] [Indexed: 11/29/2023] Open
Abstract
Enantio-discrimination and spin-dependent electrochemistry (SDE), as a manifestation of the chirality-induced spin selectivity (CISS) effect, are important phenomena that can be probed by "chiral" electrochemistry. Here, we prepared chiralized surfaces of gold and nickel, to serve as working electrodes, through effective chemisorption of enantiopure dimethyl-bis(ethylenedithio)-tetrathiafulvalene (DM-BEDT-TTF) 1, tetramethyl-bis(ethylenedithio)-tetrathiafulvalene (TM-BEDT-TTF) 2, and their capped silver nanoparticle (AgNPs) aggregate by simple incubation of the metallic substrates. The effective chemisorption was checked by means of ultrahigh vacuum x-ray photoelectron spectroscopy (XPS) and by electro-desorption experiments, i.e., cyclic voltammetry (CV) scans showing a first electro-desorption peak at about -1.0 V. The Au|1 and Au|2 chiral electrodes were successfully used in CV experiments exploiting chiral redox probes. Finally, the hybrid interfaces Ni|enantiopure 1 or 2|AgNPs served as working electrodes in SDE experiments. In particular, the hybrid chiral interfaces Ni|(R)-2|AgNPs and Ni|(S)-2|AgNPs exhibited a significant spin-filtering ability, as a manifestation of the CISS effect, with average spin polarization values of 15%.
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Rikken GLJA, Avarvari N. Comparing Electrical Magnetochiral Anisotropy and Chirality-Induced Spin Selectivity. J Phys Chem Lett 2023; 14:9727-9731. [PMID: 37879090 DOI: 10.1021/acs.jpclett.3c02546] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
The combination of chirality and magnetism has steadily grown over the past decennia into an area of intense research that evolves around two distinct manifestations and in two nonoverlapping communities: electrical magnetochiral anisotropy (eMChA) and chirality-induced spin-selectivity (CISS). Here, we discuss the similarities and differences of these two effects. Whereas the original CISS reports suggest an intimate relation with eMChA, magnetoresistance (MR) results on two-terminal chiral devices attributed to CISS have symmetry properties that are different from those of eMChA. At the same time, the magnitudes of CISS MR and eMChA turn out to be similar when normalized to current density and spin polarization, suggesting a common underlying mechanism.
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Mastropasqua Talamo M, Cauchy T, Zinna F, Pop F, Avarvari N. Tuning the photophysical and chiroptical properties of [4]helicene-diketopyrrolopyrroles. Chirality 2023; 35:805-816. [PMID: 37203869 DOI: 10.1002/chir.23593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/28/2023] [Accepted: 05/06/2023] [Indexed: 05/20/2023]
Abstract
Synthesis and functionalization of diketopyrrolo[3,4-c]pyrrole (DPP) derivatives containing chiral groups able to induce a strong chiral perturbation of the DPP core are still a challenging task. We report in this work the straightforward preparation of four bis([4]helicene)-DPP and bis([4]thiahelicene)-DPP dyes upon the condensation of 2-CN-[4](thia)helicene precursors, followed by their N-alkylation by nucleophilic substitution (compounds 9-11) or by a Mitsunobu-type strategy (compound 12). Compound 12, which contains sec-phenylethyl groups attached to the nitrogen atoms, has been obtained as (R,R) and (S,S) enantiomers. The four DPP-helicenes are luminescent in solution, while the N-benzyl (10) and N-sec-phenethyl (12) are emissive in the solid state as well. The chiroptical properties of compound 12 in solution and in the solid state indicate a strong chiral perturbation provided by the α-stereogenic centres, in spite of the stereodynamic nature of the [4]helicene flanking units.
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Oggianu M, Abhervé A, Marongiu D, Quochi F, Galán-Mascarós JR, Bertolotti F, Masciocchi N, Avarvari N, Mercuri ML. Terbium and Europium Chlorocyananilate-Based 2D Coordination Polymers. Molecules 2023; 28:6453. [PMID: 37764229 PMCID: PMC10535540 DOI: 10.3390/molecules28186453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 08/29/2023] [Accepted: 09/01/2023] [Indexed: 09/29/2023] Open
Abstract
Two-dimensional layered coordination polymers based on the hetero-substituted 3-chloro-6-cyano-2,5-dihydroxybenzoquinone ligands, hereafter ClCNAn2- anilate, and LnIII ions (Tb and Eu) are reported. Compounds 1 and 2, formulated as Ln2(ClCNAn)3(DMSO)6 (LnIII = Tb, 1; Eu, 2), and their related intermediates 1' and 2', formulated as Ln2(ClCNAn)3(H2O)x·yH2O (x + y likely = 12, Ln = Tb, 1'; and Eu, 2'), were prepared by a conventional one-pot reaction (the latter) and recrystallized from DMSO solvent (the former). Polyhydrated intermediates 1' and 2' show very similar XRPD patterns, while, despite their common stoichiometry, 1 and 2 are not isostructural. Compound 1 consists of a 2D coordination framework of 3,6 topology, where [Tb(DMSO)3]III moieties are bridged by three bis-chelating ClCNAn2- ligands, forming distorted hexagons. Ultrathin nanosheets of 1 were obtained by exfoliation via the liquid-assisted sonication method and characterized by atomic force microscopy, confirming the 2D nature of 1. The crystal structure of 2, still showing the presence of 2D sheets with a "hexagonal" mesh and a common (3,6) connectivity, is based onto flat, non-corrugated slabs. Indeed, at a larger scale, the different "rectangular tiles" show clear roofing in 1, which is totally absent in 2. The magnetic behavior of 1 very likely indicates depopulation of the highest crystal-field levels, as expected for TbIII compounds.
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Voigt J, Martin K, Neziri E, Baljozović M, Wäckerlin C, Avarvari N, Ernst KH. Highly Stereospecific On-Surface Dimerization into Bishelicenes: Topochemical Ullmann Coupling of Bromohelicene on Au(111). Chemistry 2023; 29:e202300134. [PMID: 36856040 DOI: 10.1002/chem.202300134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/24/2023] [Accepted: 02/28/2023] [Indexed: 03/02/2023]
Abstract
The on-surface dimerization into bis(hexahelicene) on a gold(111) surface has been studied by means of scanning tunneling microscopy and time-of-flight secondary mass spectrometry. C-C Ullmann coupling of (rac)-2-bromo-hexahelicene leads to formation of the (M,M)- and (P,P)- diastereomers of 2,2'-bis(hexahelicene), whilst formation of the (M,P)-diastereomer is not observed. Upon cooling, the bis(hexahelicene) aggregates into an ordered two-dimensional lattice with partly randomly distributed enantiomers. The highly specific diastereomeric coupling is explained by the surface alignment of educt in combination with the strong steric overcrowding in a possible surface-confined (M,P)-product.
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Solano F, Auban-Senzier P, Olejniczak I, Barszcz B, Runka T, Alemany P, Canadell E, Avarvari N, Zigon N. Bis(Vinylenedithio)-Tetrathiafulvalene-Based Coordination Networks. Chemistry 2023; 29:e202203138. [PMID: 36349992 DOI: 10.1002/chem.202203138] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/07/2022] [Accepted: 11/07/2022] [Indexed: 11/10/2022]
Abstract
Novel coordination polymers embedding electroactive moieties present a high interest in the development of porous conducting materials. While tetrathiafulvalene (TTF) based metal-organic frameworks were reported to yield through-space conducting frameworks, the use of S-enriched scaffolds remains elusive in this field. Herein is reported the employment of bis(vinylenedithio)-tetrathiafulvalene (BVDT-TTF) functionalized with pyridine coordinating moieties in coordination polymers. Its combination with various transition metals yielded four isostructural networks, whose conductivity increased upon chemical oxidation with iodine. The oxidation was confirmed in a single-crystal to single-crystal X-ray diffraction experiment for the Cd(II) coordination polymer. Raman spectroscopy measurements and DFT calculations confirmed the oxidation state of the bulk materials, and band structure calculations assessed the ground state as an electronically localized antiferromagnetic state, while the conduction occurs in a 2D manner. These results are shedding light to comprehend how to improve through-space conductivity thanks to sulfur enriched ligands.
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Bogdan A, Moraru IT, Auban-Senzier P, Grosu I, Pop F, Avarvari N. Chiral Bis(tetrathiafulvalene)-1,2-cyclohexane-diamides. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27206926. [PMID: 36296517 PMCID: PMC9611696 DOI: 10.3390/molecules27206926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 11/30/2022]
Abstract
Chiral bis(TTF) diamides have been obtained in good yields (54-74%) from 1,2-cyclohexane-diamine and the corresponding TTF acyl chlorides. The (R,R)-1 and (S,S)-1 enantiomers have been characterized by circular dichroism and the racemic form by single-crystal X-ray diffraction. The neutral racemic bis(TTF)-diamide shows the formation of a pincer-like framework in the solid state, thanks to the intramolecular S···S interactions. The chemical oxidation in a solution using FeCl3 provides stable oxidized species, while the electrocrystallization experiments provided radical cation salts. In particular, single-crystal resistivity measurements on the racemic donor with AsF6- as a counterion demonstrate semiconductor behavior in this material. The DFT and TD-DFT calculations support the structural and chiroptical features of these new chiral TTF donors.
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Guy L, Oda R, Avarvari N, Crassous J, Berova N, Pescitelli G, Trapp O, Collina S. Special issue: Chirality in France. Chirality 2022; 34:697-698. [PMID: 35238416 DOI: 10.1002/chir.23432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 02/16/2022] [Indexed: 11/06/2022]
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Abhervé A, Mastropasqua Talamo M, Vanthuyne N, Zinna F, Di Bari L, Grasser M, Le Guennic B, Avarvari N. Chiral Emissive Lanthanide Complexes from Enantiopure [6]Helicene‐bis(pyrazolyl)‐pyridine Ligands. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Plyuta N, Petrusenko SR, Kokozay V, Cauchy T, Lloret F, Julve M, Cano J, Avarvari N. Field-induced mononuclear cobalt(II) single-molecule magnet (SMM) based on a benzothiadiazole-ortho-vanillin ligand. Dalton Trans 2022; 51:4760-4771. [DOI: 10.1039/d1dt04274b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A unique π-conjugated benzothiadiazole-ortho-vanillin ligand (HL), characterized by single crystal X-ray diffraction and DFT calculations, has been prepared by condensation between 4-amino-benzothiadiazole (BTD) and ortho-vanillin. Its reaction with cobalt(II) acetate...
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Mroweh N, Cauchy T, Vanthuyne N, Avarvari N. Chiral diethyl-EDT-TTF and tetraethyl-BEDT-TTF: synthesis, structural characterization, radical cation salt and charge transfer complexes. CrystEngComm 2022. [DOI: 10.1039/d2ce00857b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The chiroptical and structural properties of the chiral tetrathiafulvalene donors DE-EDT-TTF and TE-BEDT-TTF, which provided crystalline radical cation salts and charge transfer complexes, have been experimentally investigated and supported by DFT and TD-DFT calculations.
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zigon N, Avarvari N. [4]Helicene based anions in electrocrystallization with tetrachalcogenafulvalene donors. CrystEngComm 2022. [DOI: 10.1039/d2ce00091a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electrocrystallization is an ubiquitous tool for the assembly of ions formed in situ from electroactive precursors into ordered crystalline macroscopic assemblies. Using tetrachalcogeno-fulvalene derivatives, many conducting and superconducting materials have...
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Baudillon M, Cauchy T, Vanthuyne N, Avarvari N, Pop F. Configurationally stable dithia[7]helicene and dithia-quasi[8]circulene fused dithiolones. Org Chem Front 2022. [DOI: 10.1039/d2qo00921h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Stereochemically stable dithia[7]helicene and dithia-quasi[8]circulene decorated with 1,3-dithiol-2-one motifs were synthesized by simple and double oxidative dehydrocyclisation.
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