Chemistry, Volume 4, Issue 2 (June 2022) – 26 articles

Electrochemical synthesis suggested a mild, green and atom-efficient route to interesting and useful molecules, thus avoiding harsh chemical oxidizing and reducing agents used in traditional synthetic methods. Organic electrochemistry offers an excellent alternative to conventional methods of organic synthesis and creates a modern tool for carrying out organic synthesis, including cascade and multicomponent ones. In this research, a novel electrocatalytic multicomponent transformation was found: the electrochemical multicomponent assembly of arylaldehydes, N,N′-dimethylbarbituric acid and 4-hydroxy-6-methyl-2H-pyran-2-one in one pot reaction was carried out in alcohols in an undivided cell in the presence of alkali metal halides with the selective formation of substituted unsymmetrical 1′,3′,6-trimethyl-3-aryl-2′H,3H,4H-spiro[furo[3,2-c]pyran-2,5′-pyrimidine]-2′,4,4′,6′(1′H,3′H)-tetraones in 73–82% yields. This new electrocatalytic process is a selective, facile and efficient way to obtain spiro[furo[3,2-c]pyran-2,5′-pyrimidines]. According to screening molecular docking data using a self-made Python script in Flare, all synthesized compounds may be prominent for different medical applications, such as breast cancer, neurodegenerative diseases and treatments connected with urinary tract, bones and the cardiovascular system. Full article

In the present work, the interaction strength of Carbon Monoxide (CO) with a set of forty-two, strategically selected, functionalized benzenes was calculated. Our ab initio calculations at the MP2/6-311++G** level of theory reveal that phenyl hydrogen sulfate (-OSO₃H) showed the highest interaction with CO (−19.5 kJ/mol), which was approximately three times stronger compared with the unfunctionalized benzene (−5.3 kJ/mol). Moreover, the three top-performing functional groups (-OSO₃H, -OPO₃H₂, -SO₃H) were selected to modify the organic linker of IRMOF-8 and test their ability to capture CO at 298 K for a wide pressure range. Our Grand Canonical Monte Carlo (GCMC) simulations showed a significant increase in the CO uptake in the functionalized MOFs compared with the parent IRMOF-8. It is distinctive that for the volumetric uptake, a 60× increase was observed at 1 bar and 2× was observed at 100 bar. The proposed functionalization strategy can be applied for improving the CO uptake performance not only in MOFs but also in various other porous materials. Full article

Mechanochemistry is a method that can cover the energy demand of reaction pathways between solid materials. This requires enough energy to maintain the reactions between the starting materials. This is called “high-energy milling”. In our case, a planetary ball mill provided the required energy. Using the Burgio-equation, the required energy is determinable; the energy released during a single impact of a milling ball (E_b), as well as during the whole milling process (E_cum). The aim of this work was the one-step production of BaTiO₃ from BaO and TiO₂ starting materials. Whereas during mechanochemical reactions it is possible to produce nanoparticles of up to 10 nm, the essence of this study is to develop the preparation of BaTiO₃ with a perovskite structure even without subsequent heat treatment, since sintering at high temperatures is associated with a rapid increase in the size of the particles. By describing the synthesis parameters and their energy values (E_b and E_cum), it is possible to transpose experimental conditions, so that in the case of other types of planetary ball mills or grinding vessel made of other materials, the results can be used. In this study, the mechanical treatment was carried out with a Fritsch Pulverisette-6 planetary ball mill and the transformation of the starting materials was investigated by X-ray diffractometric, Raman and Energy-dispersive X-ray spectroscopic, and transmission electron microscopic measurements. Full article

We investigated the adsorption properties and the dielectric behavior of a very well-known metal-organic framework (MOF), namely Cu₃(BTC)₂ (known as HKUST-1; BTC = 1,3,5-benzenetricarboxylate), before and after protection with some amines. This treatment has the purpose of reducing the inherent hygroscopic nature of HKUST-1, which is a serious drawback in its application of as low-dielectric-constant (low-κ) material. Moreover, we investigated the structure of HKUST-1 under a strong electric field, confirming the robustness of the framework. Even under dielectric perturbation, the water molecules adsorbed by the MOF remained almost invisible to X-ray diffraction, apart from those directly bound to the metal ions. However, the replacement of H₂O with a more visible guest molecule such as CH₂Br₂ made the cavity that traps the guest more visible. Finally, in this work we demonstrate that impedance spectroscopy is a valuable tool for identifying water sorption in porous materials, providing information that is complementary to that of adsorption isotherms. Full article

Arylboronic acids are commonly used in modern organic chemistry to form new C–C and C–heteroatom bonds. These activated organic synthons show reactivity with heteroatoms in a range of substrates under ambient oxidative conditions. This broad reactivity has limited their use in protic, renewable solvents like water, ethanol, and methanol. Here, we report our efforts to study and optimize the activation of arylboronic acids by a copper(II) N-heterocyclic carbene (NHC) complex in aqueous solution and in a range of alcohols to generate phenol and aryl ethers, respectively. The optimized reactivity showcases the ability to make targeted C–O bonds, but also identifies conditions where water and alcohol activation could be limiting for C–C and C–heteroatom bond-forming reactions. This copper(II) complex shows strong reactivity toward arylboronic acid activation in aqueous medium at ambient temperature. The relationship between product formation and temperature and catalyst loading are described. Additionally, the effects of buffer, pH, base, and co-solvent are explored with respect to phenol and ether generation reactions. Characterization of the new copper(II) NCN-pincer complex by X-ray crystallography, HR-MS, cyclic voltammetry, FT-IR and UV-Vis spectral studies is reported. Full article

In this work, we study the kinetics of thermal decomposition of MgCO₃ in the form of particles of known size. In the experiments, the material is heated to a known temperature in a vacuum oven, and it is characterized, both before and after heating, by infrared spectroscopy and gravimetry. The agreement between the results of the two techniques is excellent. These results are rationalized by means of a model based on Languir’s law, and the comparison with the experiments allows us to estimate the activation energy of the process. The reabsorption of atmospheric water by the oxide is shown spectroscopically, finding that is strongly influenced by the temperature of the process. Full article

Polynuclear heterobimetallic coordination cages in which different metal cations are connected within a ligand scaffold are known to adopt a variety of polyhedral architectures, many of which display interesting functions. Within the extensive array of coordination cages incorporating Fe(II) centres reported so far, the majority contain low-spin (LS) Fe(II), with high-spin (HS) Fe(II) being less common. Herein, we present the synthesis and characterisation of a new tetradecanuclear heterobimetallic [Fe₈Pd₆L₈](BF₄]₂₈ (1) cubic cage utilising the metalloligand approach. Use of the tripodal tris-imidazolimine derivative (2) permitted the formation of the tripodal HS Fe(II) metalloligand [FeL](BF₄)₂·CH₃OH (3) that was subsequently used to form the coordination cage 1. Magnetic and structural analyses gave insight into the manner in which the HS environment of the metalloligand was transferred into the cage architecture along with the structural changes that accompanied its occupancy of the eight corners of the discrete cubic structure. Full article

Lithium oligo-α-pyridylamides are useful intermediates in coordination chemistry. Upon trans-metalation they have afforded a variety of extended metal atom chains (EMACs), which are currently investigated as molecular wires and single-molecule magnets. However, structural information on this class of compounds is scarce. Two trilithium salts of a new, sterically encumbered oligo-α-pyridylamido ligand were isolated in crystalline form and structurally characterized in the solid state and in solution. Lithiation of N²-(trimethylsilyl)-N⁶-{6-[(trimethylsilyl)amino]pyridin-2-yl}pyridine-2,6-diamine (H₃L) with n-BuLi in thf yielded dimeric adduct [Li₆L₂(thf)₆] (1), which was crystallized from n-hexane/thf as 1·C₆H₁₄. Crystals of a tetra-thf solvate with formula [Li₆L₂(thf)₄] (2) were also obtained. The compounds feature two twisted L³⁻ ligands exhibiting a cis-cis conformation and whose five nitrogen donors are all engaged in metal coordination. The six Li⁺ ions per molecule display coordination numbers ranging from 3 to 5. Compound 1·C₆H₁₄ was investigated by multinuclear 1D and 2D NMR spectroscopy, including ¹H DOSY experiments, which indicated retention of the dimeric structure in benzene-d₆ solution. To the best of our knowledge, 1 and 2 are the longest-chain lithium oligo-α-pyridylamides structurally authenticated so far, thereby qualifying as appealing intermediates to access high-nuclearity EMACs by trans-metalation. Full article

Supramolecular metal–organic cages, a class of molecular containers formed via coordination-driven self-assembly, have attracted sustained attention for their applications in catalysis, due to their structural aesthetics and unique properties. Their inherent confined cavity is considered to be analogous to the binding pocket of enzymes, and the facile tunability of building blocks offers a diverse platform for enzyme mimics to promote organic reactions. This minireview covers the recent progress of supramolecular metal–organic coordination cages for boosting organic reactions as reaction vessels or catalysts. The developments in the utilizations of the metal–organic cages for accelerating the organic reactions, improving the selectivity of the reactions are summarized. In addition, recent developments and successes in tandem or cascade reactions promoted by supramolecular metal–organic cages are discussed. Full article

Recently, catalysts with hydrotalcites and hydrotalcite-derived compounds have attracted particular interest due to their specific properties, mostly well-developed texture, high thermal stability, and favorable acid–base properties. In this work, we report the investigation of ammonia synthesis on barium-promoted cobalt catalysts supported on hydrotalcite-derived Mg-Al mixed oxides with different Mg/Al molar ratios. The obtained catalysts were characterized using TGA-MS, nitrogen physisorption, XRPD, TEM, STEM-EDX, H₂-TPD, CO₂-TPD, and tested in ammonia synthesis (470 °C, 6.3 MPa, H₂/N₂ = 3). The studies revealed that the prepared Mg-Al mixed oxides are good candidates as support materials for Co-based catalysts. However, interestingly, the support composition does not influence the activity of Ba/Co/Mg-Al catalysts. The change in Mg/Al molar ratio in the range of 2–5 did not significantly change the catalyst properties. All the catalysts are characterized by similar textural, structural, and chemisorption properties. The similar density of basic sites on the surface of the studied catalysts was reflected in their comparable performance in ammonia synthesis. Full article

Converting solar energy to chemical energy through a photocatalytic reaction is an efficient technique for obtaining a clean and affordable source of energy. The main problem with solar photocatalysts is the recombination of charge carriers and the large band gap of the photocatalysts. The plasmonic noble metal coupled with a semiconductor can give a unique synergetic effect and has emerged as the leading material for the photocatalytic reaction. The LSPR generation by these kinds of materials has proved to be very efficient in the photocatalytic hydrolysis of the hydrogen-rich compound, photocatalytic water splitting, and photocatalytic degradation of organic dyes. A noble metal coupled with a low bandgap semiconductor result in an ideal photocatalyst. Here, both the noble metal and semiconductor can absorb visible light. They tend to produce an electron–hole pair and prevent the recombination of the generated electron–hole pair, which ultimately reacts with the chemicals in the surrounding area, resulting in an enhanced photocatalytic reaction. The enhanced photocatalytic activity credit could be given to the shared effect of the strong SPR and the effective separation of photogenerated electrons and holes supported by noble metal particles. The study of plasmonic metal nanoparticles onto semiconductors has recently accelerated. It has emerged as a favourable technique to master the constraint of traditional photocatalysts and stimulate photocatalytic activity. This review work focuses on three main objectives: providing a brief explanation of plasmonic dynamics, understanding the synthesis procedure and examining the main features of the plasmonic metal nanostructure that dominate its photocatalytic activity, comparing the reported literature of some plasmonic photocatalysts on the hydrolysis of ammonia borane and dye water treatment, providing a detailed description of the four primary operations of the plasmonic energy transfer, and the study of prospects and future of plasmonic nanostructures. Full article

Structural preferences of (1,3,5-cyclooctatriene) hexacarbonyl diiron [(C₈H₁₀)Fe₂(CO)₆] and cycloheptatriene hexacarbonyl diiron [(C₇H₈)Fe₂(CO)₆] were explored using density functional theory (DFT) computations. DFT computations together with experimental results demonstrated that structure with the [η³, (η¹, η²)] mode is the preferred structure in (C₈H₁₀)Fe₂(CO)₆, and the [η³,η³] mode is preferred in (C₇H₈)Fe₂(CO)₆. For (C₈H₁₀)Fe₂(CO)₆, the conversion between the structures with [η³, (η¹, η²)] mode and the [η³, η³] mode is prevented by the relatively high activation barrier. (C₈H₁₀)Fe₂(CO)₆ is indicated as a fluxional molecule with a Gibbs free energy of activation of 8.5 kcal/mol for its ring flicking process, and an excellent linear correlation (R² = 0.9909) for the DFT simulated ¹H-NMR spectra was obtained. Results provided here will develop the understanding on the structures of other polyene analogs. Full article

The study on the synthesis of zeolites, including both the development of novel techniques of synthesis and the discovery of new zeolitic frameworks, has a background of several decades. In this context, the application of organic structure-directing agents (SDAs) is one of the key factors having an important role in the formation of porous zeolitic networks as well as the crystallization process of zeolites. There are various elements that are needed to be explored for elucidating the effects of organic SDAs on the final physicochemical properties of zeolites. Although SDAs were firstly used as pore generators in the synthesis of high-silica zeolites, further studies proved their multiple roles during the synthesis of zeolites, such as their influences on the crystallization evolution of zeolite, the size of the crystal and the chemical composition, which is beyond their porogen properties. The aim of this mini review is to present and briefly summarize these features as well as the advances in the synthesis of new SDAs during the last decades. Full article

The binding energies of 121 complexes between anions and bis(cyclopeptides) differing in the structure and the number of linking units between the two cyclopeptide rings were analyzed. These Gibbs free energies were obtained in earlier work for different anions, under different conditions, and with different methods. The multiparametric analysis of a subset of 42 binding energies afforded linear relationships that allowed the relatively reliable estimation of the iodide and sulfate affinity of three structurally related bis(cyclopeptides) in water/methanol and water/acetonitrile mixtures at different solvent compositions. Three parameters were required to achieve a satisfactory correlation, namely, the Gibbs free energy of transferring the respective anion from water into the solvent mixture in which complex stability was determined, and the Kamlet–Taft parameters α and β. Based on these relationships, the anion affinities of the other bis(cyclopeptides) were evaluated, giving rise to a set of energy increments that allow quantifying the effects of the linker structure or the nature of the anion on binding affinity relative to the reference system. Full article

Different extraction pH values obtain polysaccharides with tailored structures and novel functionalities. This study investigated the influence of different extraction pH values (4.2, 6.8, and 9.2) on the physicochemical compositions and structural and functional properties of okra leaf polysaccharides (OLPs). The extraction yield (2.74–7.34%), molecular weights (68.5–85.4 kDa), total sugar contents (64.87–95.68%), degree of acetylation (18.28–22.88%), and methylation (8.97–15.20%) of OLPs varied significantly (p < 0.05). The monosaccharide composition reflected OLPs as pectic polysaccharides, with varied compositions of galacturonic acid, galactose, rhamnose, and arabinose. However, the differences in their sugar molar ratios, such as their side-chain and backbone chain compositions, greatly affected their functional properties. Additionally, notable differences due to extraction pH were observed in physical properties, thermal stability, and crystallinity. However, FTIR and NMR spectra revealed that extraction pH had negligible effects on the primary structure of OLPs. All OLPs showed non-Newtonian fluid behavior in the aqueous system with different apparent viscosities correlating with their molecular weights. Furthermore, the OLPs fractions stabilized oil-in-water emulsions differently and had distinct radical scavenging activities related to their compositions. This study provides a basis for selecting appropriate extraction pH to prepare OLPs with specific characteristics and applications in food-related disciplines. Full article

A ditopic nitrogen ligand (E)-N′-(pyridin-4-ylmethylene)isonicotinohydrazide (L) containing both divergent pyridyl coordination sites and a hydrogen-bonding hydrazide–hydrazone moiety was synthesized. The Co(NCS)₂-mediated self-assembly of L has resulted in the synthesis of a novel 3-dimensional (3D) supramolecular framework (1) that features both coordination and hydrogen bonding interactions. X-ray structural analysis reveals the formation and coordination mode of 1 in the solid state. The rational utilization of coordination bonds and hydrogen bonding interactions is confirmed and responsible for constructing the 3D materials. Catalytic studies using 1 in the presence of an activator are performed for the hydroboration and hydrosilylation reactions of ketones and aldehydes, and the results are compared with previously reported cobalt-based polymeric catalysts. Full article

This work reports the in situ instrumentation from manufacturing to loading of a henequen fiber woven-bioepoxy composite. Continuous monitoring was performed by means of fiber Bragg gratings (FBG) with the aim of tracking the curing behavior of the biolaminate by vacuum-assisted resin infusion (VARI). The instrumented composite was later tested mechanically under bending. Among the results obtained, micro-deformations were detected as a consequence of curing residual stresses, and when tested, the FBG data had similarity with the strain calculated according to the ASTM D7264/D7264M standard. Full article

Oxidative dehydrogenation (ODH) reaction has emerged as a promising route for converting 1-butene to value-added 1,3-butadiene (BD). However, the low BD selectivity of the current catalysts (≤40%) and high steam input are now the challenge of this process. Here, we demonstrate the fabrication BiMo oxides immobilized on carbon nanotubes (BiMo/CNTs), employing the sol–gel method, as a novel catalyst for the ODH of 1-butene without steam in a fixed-bed reactor. The catalytic performances of BiMo/CNTs with different compositions in the absence of steam were investigated. When BiMo/CNTs at a molar ratio of 0.018 were employed in the ODH of 1-butene under reaction conditions of 440 °C, 1-butene/oxygen = 1/0.8, and no steam, the optimal BD yield was achieved as high as 52.2%. Under this reaction condition, the catalyst maintains good stability without steam after 10 h of reaction. This work not only promotes the application of carbon materials in oxidative dehydrogenation reaction, but also accelerates the production of 1,3-butadiene in a more economical way. Full article

By virtue of their unique physicochemical properties, gold nanoparticles (AuNPs) have gained significant interest in a broad range of biomedical applications such as sensors, diagnosis, and therapy. AuNPs are generally synthesized via different conventional physical and chemical methods, which often use harmful chemicals that induce health hazards and pollute the environment. To overcome these issues, green synthesis techniques have evolved as alternative and eco-friendly approaches to the synthesis of environmentally safe and less-expensive nanoparticles using naturally available metabolites from plants and microorganisms such as bacteria, fungi, and algae. This review provides an overview of the advances in the synthesis of AuNPs using different biological resources with examples, and their profound applications in biomedicine. A special focus on the biosynthesis of AuNPs using different medicinal plants and their multifunctional applications in antibacterial, anti-inflammatory, and immune responses are featured. Additionally, the applications of AuNPs in cancer theranostics, including contrast imaging, drug delivery, hyperthermia, and cancer therapeutics, are comprehensively discussed. Moreover, this review will shed light on the importance of the green synthesis approach, and discuss the advantages, challenges, and prospects in this field. Full article

Quinoidal oligothiophenes have received considerable attention as interesting platforms with remarkable amphoteric redox behavior associated with their diradical character increasing with the conjugation lengths. In this work, we considered a family of quinoidal oligothiophenes bearing cyano-ester terminal groups and characterized them by UV-Vis-NIR absorption and Raman spectroscopy measurements at different excitation wavelengths. The experimental investigation is complemented by quantum-chemical studies to assess the quality of computed density functional theory (DFT) ground state structures and their influence on predicted Raman intensities. In addition, resonance conditions with the optically active HOMO→LUMO transition as well as with the more elusive state dominated by the doubly excited HOMO,HOMO→LUMO,LUMO configuration, are determined with DFT-MRCI calculations and their contributions to Raman activity enhancement are discussed in terms of computed vibrational Huang–Rhys (HR) factors. Full article

The study showed that the interaction of the product of centrifugal thermal activation of gibbsite with an aqueous solution of magnesium nitrate at a cationic ratio Mg:Al = 1:2 leads to the formation of mixed double hydroxides both under hydrothermal treatment at 150 °C and at room temperature. The subsequent thermal treatment at 550 °C of the product of mild interaction leads to ~90% alumina-magnesia spinel and ~10% MgO, while the treatment of the hydrothermal interaction product leads to ~100% spinel with the stoichiometric composition MgAl₂O₄. The obtained spinel samples possess a high specific surface area (above 100 m²/g) and a hierarchical pore structure formed by the micron-level particles of different sizes (1–2 and 10–20 μm) consisting of ~70 nm crystallites with ~3 nm pores; the samples differ mostly in the total volume and quantitative ratio of the pores. The samples have Lewis acid sites of moderate strength on the surface, the amount of which is much lower to how it is when compared with a sample prepared by precipitation in that they also differ by quantity from each other as well (503 μmol/g for stoichiometric spinel and 304 μmol/g for sample with admixture of MgO). As the calcination temperature is raised to 850 °C, the acidity decreases—only weak Lewis acid sites are observed, the amount of which is also higher for stoichiometric spinel (161 and 39 μmol/g, respectively). The method proposed for the synthesis of alumina-magnesia systems provides a high dispersion and a much lower surface acidity for the oxides; in addition, it minimizes or completely excludes wash water, in distinction to the precipitation method. Full article

Zeolites have been successfully applied as catalysts in the pyrolysis of plastics to obtain valuable lower molecular weight hydrocarbon compounds. In the present work, mordenite was directly synthesized and chemically modified from commercial mordenite to increase pore volume. For the first time, the performance of these mordenites was compared with that of an alkali-treated ZSM-5 as catalysts for assisting the pyrolysis of simulated urban plastic waste. The investigated zeolites were: (i) as-supplied synthetic ZSM-5 (ZSM-5/AS); (ii) 0.2 M NaOH treated ZSM-5 (ZSM-5/02); (iii) as-supplied mordenite (MOR/AS); (iv) 0.2 M NaOH treated mordenite (MOR/02); and (v) synthetic lab-developed mordenite (MOR/SD). The modified and synthesized zeolites were individually applied as catalysts in the 700 °C pyrolyzes of combined polyethylene, polypropylene, and polystyrene wastes in a mixture simulating most plastics found in Rio de Janeiro (Brazil) city garbage composition. X-ray diffraction revealed crystallite sizes of all zeolites in a nanometric range from 17 to 43 nm. Textural analysis disclosed the alkali-treated ZSM-5/02 with a superior external surface area, 153 m²/g, and mesopore volume equal to 0.253 cm³/g. Lower values were obtained by MOR/02 (39 m²/g and 0.072 cm³/g). The pyrolysis of the plastic mixture with ZSM-5/02 presented a lower initial degradation temperature, 387 °C, followed by MOR/02, with 417 °C. The ZSM-5/02 catalyst obtained the highest conversion in the pyrolysis of the plastic mixture, totaling 49.2%. However, pyrolysis assisted by the MOR/02 catalyst showed the largest fraction (81.5%) of light hydrocarbons. Full article

Visible-light-driven heterostructure Ag/Bi₂WO₆ nanocomposites were prepared using a hydrothermal method followed by the photodeposition of Ag on Bi₂WO₆. A photocatalyst with a different molar ratio of Ag to Bi₂WO₆ (1:1, 1:2 and 2:1) was prepared. The catalytic performance of Ag/Bi₂WO₆ towards the photocatalytic oxidation of rhodamine B (RhB) and methylene blue (MB) was explored. Interestingly, the Ag/Bi₂WO₆ (1:2) catalyst exhibited superior performance; it oxidized 83% of RhB to Rh-110 and degraded 68% of MB in 90 min. This might be due to the optimum amount of Ag nanoparticles, which supported the rapid generation and transfer of separated charges from Bi₂WO₆ to Ag through the Schottky barrier. An excess of Ag on Bi₂WO₆ (1:1 and 2:1) blocked the active sites of the reaction and did not produce the desired result. The introduction of Ag on Bi₂WO₆ improved the electrical conductivity of the composite and lowered the recombination rate of charge carriers. Our work provides a cost-effective route for constructing high-performance catalysts for the degradation of toxic dyes. Full article

The development of widely applicable methods for the synthesis of C-C-bonded nanostructures on inert and insulating surfaces is a challenging yet rewarding milestone in the field of on-surface synthesis. This would enable studies of nearly unperturbed covalent nanostructures with unique electronic properties as graphene nanoribbons (GNR) and π-conjugated 2D polymers. The prevalent Ullmann-type couplings are almost exclusively carried out on metal surfaces to lower the temperature required for initial dehalogenation well below the desorption threshold. To overcome the necessity for the activation of monomers on the target surface, we employ a recently developed Radical Deposition Source (RaDeS) for the direct deposition of radicals onto inert surfaces for subsequent coupling by addition reactions. The radicals are generated en route by indirect deposition of halogenated precursors through a heated reactive tube, where the dehalogenation reaction proceeds. Here, we use the ditopic 6,11-diiodo-1,2,3,4-tetraphenyltriphenylene (DITTP) precursor that afforded chevron-like GNR on Au(111) via the usual two-staged reaction comprised of monomer-coupling into covalent polymers and subsequent formation of an extended GNR by intramolecular cyclodehydrogenation (CDH). As a model system for inert surfaces, we use Ag(111) passivated with a closed monolayer of chemisorbed iodine that behaves in an inert manner with respect to dehalogenation reactions and facilitates the progressive coupling of radicals into extended covalent structures. We deposit the DITTP-derived biradicals onto both iodine-passivated and pristine Ag(111) surfaces. While on the passivated surface, we directly observe the formation of covalent polymers, on pristine Ag(111) organometallic intermediates emerge instead. This has decisive consequences for the further progression of the reaction: heating the organometallic chain directly on Ag(111) results in complete desorption, whereas the covalent polymer on iodine-passivated Ag(111) can be transformed into the GNR. Yet, the respective CDH proceeds directly on Ag(111) after thermal desorption of the iodine passivation. Accordingly, future work is aimed at the further development of approaches for the complete synthesis of GNR on inert surfaces. Full article

Viruses, and in particular, RNA viruses, dominate the WHO’s current list of ten global health threats. Of these, we review the widespread and most common HIV, influenza virus, and SARS-CoV-2 infections, as well as their possible prevention by vaccination and treatments by pharmacotherapeutic approaches. Beyond the vaccination, we discuss the virus-targeting and host-targeting drugs approved in the last five years, in the case of SARS-CoV-2 in the last one year, as well as new drug candidates and lead molecules that have been published in the same periods. We share our views on vaccination and pharmacotherapy, their mutually reinforcing strategic significance in combating pandemics, and the pros and cons of host and virus-targeted drug therapy. The COVID-19 pandemic has provided evidence of our limited armamentarium to fight emerging viral diseases. Novel broad-spectrum vaccines as well as drugs that could even be applied as prophylactic treatments or in early phases of the viremia, possibly through oral administration, are needed in all three areas. To meet these needs, the use of multi-data-based precision medicine in the practice and innovation of vaccination and drug therapy is inevitable. Full article