About
132
Publications
11,791
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
2,019
Citations
Citations since 2017
Publications
Publications (132)
The straightforward access to N- or C-substituted dinitro-tetraamino-phenazines (P1-P5) is enabled in oxidative conditions via formation of two intermolecular C-N bonds from accessible 5-nitrobenzene-1,2,4-triamine precursors. The photophysical studies revealed green absorbing and orange-red emitting dyes, with enhanced fluorescence in the solid st...
The structure of the Viologen-Phenylene-Imidazole (VPI) guest, previously shown to be bound by cucurbit[7]uril (CB[7]) with binding modes depending on pH and silver ions, has been extended by adding hydrophobic groups on the two extremities of VPI before investigations of CB[7] binding by NMR, ITC, X-ray diffraction, UV-vis and fluorescence spectro...
Within the heteroacene family, azapentacenes have received much attention in organic electronic devices due to their unique physico-chemical properties. This is particularly true for the 5,14-dihydro-5,7,12,14-tetraazapentacene despite its poor solubility in organic solvents which logically hindered the study of its electrochemical behavior. Conseq...
Hybrid van der Waals heterostructures made of 2D materials and organic molecules exploit the high sensitivity of 2D materials to all interfacial modifications and the inherent versatility of the organic compounds. In this study, we are interested in the quinoidal zwitterion/MoS2 hybrid system in which organic crystals are grown by epitaxy on the Mo...
The last decade has seen a flurry of studies related to graphene nanoribbons owing to their potential applications in the quantum realm. However, little experimental work has been reported towards nanoribbons of other 2D materials. Here, we propose a universal approach to synthesize high-quality networks of nanoribbons from arbitrary 2D materials w...
Azacalix[n]arenes (ACAs) are lesser-known cousins of calix[n]arenes that contain amine bridges instead of methylene bridges, so they generally have higher flexibility due to enlarged cavities. Herein, we report a highly substituted cationic azacalix[4]arene-based covalent organic framework (ACA-COF) synthesized by the Zincke reaction under microwav...
2,5-Diamino-1,4-benzoquinonediimine (DABQDI) derivatives possessing two electron-withdrawing aromatic N-substituents can potentially exhibit a zwitterionic ground state in lieu of the expected canonical structure. It was previously shown that the use of nitroaromatics electron-withdrawing groups (EWG) could yield the quantitative formation of zwitt...
The on‐surface synthesis of metal‐organic covalent coordination networks with a dense Kagomé lattice of metallic centers is reported. Tetrahydroxyquinone and metal atoms (M = Cu or Mn) are codeposited on Ag(111) substrate to build well‐ordered 2D lattices M3C6O6. The surface is studied by scanning tunneling microscopy, low‐energy electron diffracti...
We predict two switchable one-dimensional (1D) spin-polarized semiconductors based on metal-organic coordination chains constructed out of Fe, V, and zwitterionic quinone (ZQ) molecules using first-principle density functional theoretical analysis. The Fe-ZQ coordination chain can be converted from a semiconductor to a half-metal when oxidized by c...
The last decade has seen a flurry of studies related to graphene nanoribbons owing to their potential applications in the quantum realm. However, little experimental work has been reported towards nanoribbons of other 2D materials due to the absence of synthesis routes. Here, we propose a universal approach to synthesize high-quality networks of na...
We report on the formation of a high-order commensurate (HOC) structure of 5,14-dihydro-5,7,12,14-tetraazapentacene (DHTAP) molecules on the highly corrugated Cu(110)-(2 × 1)O surface. Scanning tunnelling microscopy shows that the DHTAP molecules form a periodic uniaxial arrangement in which groups of seven molecules are distributed over exactly ni...
We report on the successful on-surface synthesis of metal-organic covalent coordination networks with a dense Kagome lattice of metallic centers. In the case of Mn centers ab-initio calculations show that the adsorbed monolayer on Ag(111) has all the characteristic features of a strictly two-dimensional (2D) ferromagnetic Kagome metal. Tetrahydroxy...
The development of methodologies to control on demand and reversibly supramolecular transformations from self‐assembled metalla‐structures requires the rational design of architectures able to answer to an applied stimulus. While solvent, concentration, guest, light, addition of a chemical have been largely explored to provide these transformations...
Azacalixphyrins are unique aromatic macrocycles featuring strong absorption from the visible to the near-infrared (NIR) spectral ranges. This work demonstrates through EPR spin-trapping experiments that the N-alkyl tetrasubstituted azacalixphyrin (ACP) can lead to the formation of carbon-centered radicals initiating for the free-radical photopolyme...
Dihydrotetraazapentacene molecules can be dehydrogenated on the surface to form tetraazapentacene by applying a high electric field between the tip of a scanning tunnelling microscope and a metallic substrate in the zero-current limit.
Starting from pyrrole-carbinol derivatives, a set of three optimized experimental conditions was used to prepare six dipyrromethanes (DPM) bearing meso-poly-halogeno-alkyl chains. On the one hand, the condensation of -anisaldehyde and the DPMs bearing a perfluoroalkyl chain (CF3, C3F7 or C7F15) produced, after oxidation, the expected trans-A2B2-por...
The electronic and magnetic properties of one-dimensional polymers of zwitterionic quinone (ZQ) molecules with 4d and 5d transition metals (TM) are studied using density functional calculations. We present the results of first-principle calculations for the electronic and magnetic properties, including the magnetic anisotropy energy (MAE) of select...
The interface between the semiconductor and the dielectric layer plays a crucial role in organic field-effect transistors (OFETs) because it is at the interface that charge carriers are accumulated and transported. In this study, four zwitterionic benzoquinonemonoimine dyes featuring alkyl and aryl N-substituents were used to cover the dielectric l...
Heat shock protein 27 (Hsp27) has an established role in tumor progression and chemo-resistance of castration-resistant prostate cancer (CRPC). Hsp27 protects eukaryotic translation initiation factor 4E (eIF4E) from degradation, thereby maintaining survival during treatment. Phenazine derivative compound #14 was demonstrated to specifically disrupt...
The first example of diamino-benzoquinonediimine bearing both electron-donating and electron-withdrawing groups on the same 6-π electron subunit was synthesized using a straightforward one pot strategy. Photophysical analysis and theoretical calculations demonstrate that this unique substitution pattern is efficient to favour the establishment of a...
Azacalixphyrins are bis-zwitterionic aromatic macrocycles that feature absorption properties in the near-infrared range. Their N-substitution is an efficient strategy for tuning the absorption maxima by stabilizing different tautomeric forms depending on the nature of the substituent (alkyl or aryl give 1-5 or 2-6 tautomers, respectively). This wor...
The transamination of oxoaminobenzoquinonemonoimine (BQI derivatives), an unconventional zwitterionic quinone, allows isolation of a series of compounds featuring electron-donating aryl auxochromes. The substitution has a very strong impact on the electrochemical and optical features, which is rationalized by theoretical calculations. Protonation a...
Recently π-d conjugated coordination polymers have received a lot of attention due to their unique material properties, although synthesis of long and defect free polymers remains challenging. Here we introduce a novel on-surface synthesis of coordination polymers with quinoidal ligand under ultra-high vacuum conditions, which enables formation of...
The on‐surface synthesis approach under UHV conditions has led us to the formation of 1D coordination π–d conjugated polymers on metal surfaces. The reaction of quinoidal ligand with different transition metals results in two distinct coordination motifs: four‐fold (Cr, Fe, Co, Ni) and two‐fold (Cu). The backbone of the Cu‐coordinated 1D chain is f...
In hydrogen bonded systems, nuclear quantum effects such as zero-point motion and tunneling can significantly affect their material properties through underlying physical and chemical processes. Presently, direct observation of the influence of nuclear quantum effects on the strength of hydrogen bonds with resulting structural and electronic implic...
We report the synthesis of a square-planar nickel complex in which the metal center is located in a NOON environment. Promoting its axial ligation triggers a spin state switching process which is accompanied by a change of the absorption properties depending on the solvent. Indeed, a strong solvatochromic shifts could be observed in the presence of...
We demonstrate that the conductance switching of benzo-bis(imidazole) molecules upon protonation depends on the lateral functional groups. The protonated H-substituted molecule shows a higher conductance than the neutral one (Gpro>Gneu), while the opposite (Gneu>Gpro) is observed for a molecule laterally functionalized by amino-phenyl groups. These...
We demonstrate that the conductance switching of benzo-bis(imidazole) molecules upon protonation depends on the lateral functional groups. The protonated H-substituted molecule shows a higher conductance than the neutral one (Gpro>Gneu), while the opposite (Gneu>Gpro) is observed for a molecule laterally functionalized by amino-phenyl groups. These...
On-surface polymerization of iron atoms and zwitterion quinone (ZQ) molecules on Ag(111) is studied experimentally under ultra-high vacuum and theoretically in the framework of density functional theory. The resulting one-dimensional (1D) polymer chain is a promising model system to study both magnetic and conductive properties in one dimension. Pr...
The fusion of two azacalixphyrin cycles absorbing in the NIR-I domain moves the absorption properties beyond 1000 nm, towards the second biological transparency window (NIR-II). The synthesis of this new...
Introducing organic semiconductors as additional building blocks into heterostructures of 2D materials widens the horizon of their applications. Organic molecules can form self‐assembled and self‐aligned crystalline nanostructures on 2D materials, resulting in well‐defined interfaces that preserve the intrinsic properties of both constituents. Thus...
In article number 1903816, Aleksandar Matković and co‐workers employ networks of self‐assembled organic nanostructures epitaxially grown on two‐dimensional hexagonal boron nitride. The work demonstrates how the polarization direction of external light can be used to realize a “light‐gate” for switching on and off the conductivity of organic nanocry...
An in-depth investigation of the optical properties of recently-synthesized linear azaacene derivatives of various electronic nature (neutral, dicationic, and zwitterionic) is presented. Our simulations include not only the determination of the vertical transitions, but also of the adiabatic energies and vibrationally-resolved spectra using the Adi...
The synthesis and properties of 1,2,3,4-tetrahydro-1,4,5,8-tetraazaanthracene (THTAA) – a heterocycle involving both >N–H donating and =N– accepting moieties – have been reinvestigated. Unlike previously reported, THTAA is a thermally stable compound that can be re-sublimed at 300–310 °C without decomposition. Controlled introduction of substituent...
The transamination reaction of 2,5-diaminobenzoquinonediimine (QDI) with ethylenediamine gave fluorescent 1,2,3,4-tetrahydropyrazino[2,3-g]quinoxaline (1). When the same reaction was carried out with N,N’-bis(aminoethyl)-1,3-propanediamine, a novel cationic quinoxalinium species (2) was isolated, which can be further condensed with p-cyanobenzaldeh...
The cover illustrates a new family of macrocycles, the azacalixquinarenes, which are built on quinoidal rings that can present either canonical or zwitterionic forms. The picturing of such electronic versatility would have been extremely arduous without the preliminary isolation of a single-crystal structure.
Azacalixquinarenes, a new family of macrocycles constituted of diaminobenzoquinone diimine units linked by dinitrobenzene rings are synthesized by selected oxidation of the parent azacalixarenes. Crystallographic analyses of two compounds demonstrated the presence of (uncharged) canonical and zwitterionic quinones within a single structure. The ele...
Near-infrared (NIR) azacalixphyrins bearing aryl substituents strongly impacting the physico-chemical properties of the macrocycles were designed, enabling hyperchromic and bathochromic shifts of the absorption compared to their N-alkylated analogues. This engineering enhances the photoacoustic response under NIR excitation, making azacalixphyrins...
We report the synthesis of a key mononuclear intermediate complex based on a quinoid ligand and its further metalation to afford the corresponding hetero-bimetallic compound that revealed unique properties. An unprecedented hetero-bimetallic effect in coordination chemistry could be indeed observed and exploited to prepare, through selective ligand...
Azacalixphyrin derivatives constitute one of the most intriguing class of macrocyclic compounds. Indeed, these isostructural and isoelectronic analogues of porphyrins intensively absorb light up to the near infrared region, exist under several tautomeric forms and present a bis-zwitterionic structure, with a central dianionic core surrounded by pos...
[This corrects the article DOI: 10.18632/oncotarget.20469.].
A series of N-substituted diamino-benzoquinone diimines featuring tunable aryl electron-withdrawing functions were synthesized. For the first time, the subtle variation of electronic richness allows to control the canonical vs zwitterionic equilibrium through the tuning of the intramolecular proton transfer. The establishment of a ground-state zwit...
The adsorption of 5,14-dihydro-5,7,12,14-tetraazapentacene (DHTAP) on Cu(110) has been investigated at different temperatures and coverages by means of scanning tunneling microscopy (STM) and low-energy diffraction (LEED). Our results show that the interaction of DHTAP with the Cu(110) surface differs considerably from that of pentacene on the same...
Dihydro-tetraaza-acenes are promising candidates for future applications in organic electronics, since these molecules form crystals through an interplay between H-bonding, dipolar, and van der Waals interactions. As a result, densely packed − π π structures – favorable for charge transport – are obtained, with exceptional stability under ambient c...
We present a combined experimental and theoretical study of electronic and optical properties of dihydro-tetraaza-acenes (DHTAn). Using a solvent-free condensation, we are able to synthesize not only DHTA5 but also the longer DHTA6 and DHTA7 molecules. We then investigate their gas-phase electronic structures by means of ab-initio density functiona...
The regioselective insertion of DDQ into a C-H bond of the 6π + 6π electron zwitterionic benzoquinonemonoimines 4a-c results in the formation of the novel chiral C-substituted quinoid ligands 11a-c. These Michael adducts feature a preserved zwitterionic form and a quaternary stereogenic carbon center as evidenced by the single crystal X-ray structu...
The actual strategy to improve current therapies in advanced prostate cancer involves targeting genes activated by androgen withdrawal, either to delay or prevent the emergence of the castration-refractory phenotype. However, these genes are often implicated in several physiological processes, and long-term inhibition of survival proteins might be...
This review covers the synthesis and properties of 2,5-diamino-1,4-benzoquinonediimines (DABQDI), and their use as ligand in coordination chemistry. Although reported more than a century ago, these molecules emerged as highly versatile ligands only from 1998, and are so far used for the synthesis of numerous complexes with remarkable properties. Th...
We describe the first isolation of N,N′-disubstituted benzoquinonediimines (QDIs) 2 which revealed drastically different properties compared to N,N′,N′′,N′′′-tetrasubstituted QDIs 1 due to the absence of N-substituents in the “upper part” of the molecule. Three major differences could be highlighted thanks to the present joint experimental and theo...
Contrasting with the well mastered azacalix[4]arene, the synthesis and characterization of azacalix[6]arene derivatives remains a challenge for chemists. In this framework, bulky n-octylamino groups appended on the 1,3-meta-diaminobenzene 2b can lead to the concomittant and straightforward one-pot formation of the azacalix[6]arene 4b and of the the...
Azacalixphyrins (ACP) constitute a new class of macrocycles isoelectronic and isostructual to porphyrins. Herein, we report the first theoretical investigation of the properties of ACP macrocycles metallated at their centre by titanium, platinum, and iron ions. We considered both the original phenyl-type ACP and new pyridyl-type forms. Our results...
On-surface synthesis under ultrahigh vacuum provides a promising strategy to control matter at the atomic level, with important implications for the design of new two-dimensional materials having remarkable electronic, magnetic, or catalytic properties. This strategy must address the problem of limited extension of the domains due to the irreversib...
The strong electron-withdrawing character of 5,15-meso-ester groups was demonstrated through the study of four fluorescent hexacoordinate phosphorus(V) meso-substituted corroles, which were characterized by various techniques including single-crystal X-ray diffraction and first-principles calculations. The nature of the remaining meso substituent t...
Pre- and postintroduction of substituents with respect to the macrocyclization step leads to previously unknown N-substituted azacalixphyrins. The stepwise synthetic approach has been studied in detail to highlight the key role of the N-substituents of the precursors and/or intermediates in terms of reactivity. Based on a combined experimental and...
A green and very efficient synthesis of N-substituted benzoquinonediimines or C-substituted benzo-bis(imidazole) derivatives is described under similar conditions. The different reaction pathway is only controlled by the nature of the primary amines, which tunes the reactivity of the intermediates.
Azacalixphyrins are particularly stable macrocycles absorbing light up to the near infrared region, which makes them good candidates for applications in a wide panel of fields. However, to date, only a very limited number of substituted azacalixphyrins are experimentally known. Herein, aiming to drive the synthesis towards the most promising substi...
Understanding the chemical nature and spectroscopic signatures of a new class of organic molecules remains a strong challenge. Azacalixphyrin, the first member of a family of strongly aromatic macrocycles absorbing in the near infrared domain, can exist under several tautomeric forms. Here, we use DFT calculations and NMR measurements to propose th...
Six tetraaza[1.1.1.1]cyclophane derivatives bearing peripheral amide groups were prepared according to two distinct synthetic strategies that depend on the connection pattern between the aryl units. NMR experiments combined with the X-ray structures of two tetraamide derivatives 4 b and 10 show that these cavitands adopt a 1,3-alternate conformatio...
A series of 2,3,7-trisubstituted phenazines were synthesized using an easy, efficient, and straightforward condensation method. These compounds were tested in vitro on human pancreatic (MiaPaCa-2) cell lines and dose response curves proved that these compounds appeared to be more cytotoxic than standard gemcitabine. Standard ethidium bromide assay...
Stepwise synthesis of linear nickel complex oligomer tapes with no need for solid-phase support has been achieved. The control of the length in flat arrays allows a fine-tuning of the absorption properties from the UV to the NIR region.
Azacalixphyrin is a recently-synthesized precursor of potentially highly versatile analogues of porphyrins. Surprisingly, this macrocyclic compound is stable to such an extend that it could be exposed to air for months as a solid or for days in solution without detectable changes. However, no rationalization of this specific property has been estab...