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We computationally studied the effect of nuclear-quadrupole interactions on the field-free impulsive alignment of different asymmetric-top molecules. Our analysis is focused on the influence of the hyperfine- and rotational-energy-level structures. These depend on the number of nuclear spins, the rotational constants, and the symmetry of the tensors involved in the nuclear spin and external field interactions. Comparing the prototypical large-nuclear-spin molecules iodobenzene, 1,2-diiodobenzene, 1,3-diiodobenzene, and 2,5-diiodobenzonitrile, we demonstrate that the magnitude of the hyperfine splittings compared to the rotational-energy splittings plays a crucial role in the spin-rotational dynamics after the laser pulse. Moreover, we point out that the impact of the quadrupole coupling on the rotational dynamics decreases when highly excited rotational states dominate the dynamics. [ABSTRACT FROM AUTHOR]

New data are presented on the resonant Auger decay of iodobenzene (C6H5I) in the region of the I 4d−1 ionization threshold. The excited molecules decay by participator and spectator processes to populate single-hole valence states and two-hole, one-particle excited states of the cation, providing new information on the structure of C6H5I+. Excitation of dissociative C6H5I (I 4d5/2,3/2−1)σ* resonances can, in principle, result in ultrafast dissociation to C6H5 + I** and the subsequent autoionization of I**, but no evidence for this process is observed. The results are compared with our recent study of the resonant Auger decay of methyl iodide (CH3I). [ABSTRACT FROM AUTHOR]

A metal‐free hypervalent iodine‐mediated C3‐trifluoropropionyloxylation of N‐substituted indoles was developed. (Bis‐trifluoropropanoate)iodobenzene was used as both the oxidant and fluorine source. The reaction was sensitive to the N‐protecting groups of the indoles. N‐acylated indoles provided 3‐trifluoropropionyloxylated indoles, while 3‐trifluoropropionyloxylated oxindoles were generated from indoles bearing N‐alkyl groups. [ABSTRACT FROM AUTHOR]

An ionic heterogenized catalyst system for Anelli oxidation has been developed using potassium 4-sulfonato-oxy-2,2,6,6-tetramethylpiperidine-1-yloxyl (TEMPO-4-sulfate) and anion exchange beads as support material. The catalytic oxidation of benzyl alcohol by bis(acetoxy)iodobenzene (BAIB) in acetonitrile with the modified beads gives a 94% yield of benzaldehyde within 60 min (batch operation). The beads give about the same conversion of benzyl alcohol in six consecutive cycles when reused after simple washing, albeit with a somewhat longer half-life time. The TEMPO entity could be removed from the beads using a sodium chloride/sodium hydroxy mixture. Reloading the beads with TEMPO-4-sulfate restored about 80% of their initial catalytic action. This exemplifies that the catalytic activity in a fixed bed can be regained without the need for cleaning and repacking the reactor. Preliminary experiments in a fixed bed show that a constant benzyl alcohol conversion of 84% over 10 residence times (as plug flow) can be achieved by the in-flow execution of the oxidation reaction. [ABSTRACT FROM AUTHOR]

The doped organic hole transport layer (HTL) is crucial for achieving high‐efficiency perovskite solar cells (PSCs). However, the traditional doping strategy undergoes a time‐consuming and environment‐dependent oxidation process, which hinders the technology upgrades and commercialization of PSCs. Here, we reported a new strategy by introducing a cascade reaction in traditional doped Spiro‐OMeTAD, which can simultaneously achieve rapid oxidation and overcome the erosion of perovskite by 4‐tert‐butylpyridine (tBP) in organic HTL. The ideal dopant iodobenzene diacetate was utilized as the initiator that can react with Spiro to generate Spiro⋅+ radicals quickly and efficiently without the participation of ambient air, with the byproduct of iodobenzene (DB). Then, the DB can coordinate with tBP through a halogen bond to form a tBP‐DB complex, minimizing the sustained erosion from tBP to perovskite. Based on the above cascade reaction, the resulting Spiro‐based PSCs have a champion PCE of 25.76 % (certificated of 25.38 %). This new oxidation process of HTL is less environment‐dependent and produces PSCs with higher reproducibility. Moreover, the PTAA‐based PSCs obtain a PCE of 23.76 %, demonstrating the excellent applicability of this doping strategy on organic HTL. [ABSTRACT FROM AUTHOR]

The article presents the results of a study of the temperature dependence of the dielectric constant ε' and the dielectric loss index ε" of the chlorobenzene-iodobenzene system at wavelengths λ = 6.32; 4.01; 3.21; 2.14; 1.18 and 0.75 V temperature range ‑40℃÷+30℃. The static dielectric constant was determined at a frequency of 7 MHz. The temperature dependence of the time of dielectric relaxation of molecules in the liquid state was determined. It was established that in the specified temperature‑frequency range the dispersion region consists of two parts. Analysis of the temperature dependence of dielectric polarization relaxation in the system chlorobenzene-iodobenzene shows that the relaxation times of the components do not depend on their short-range order. It was also discovered that the rate graph showing the dependence of the logarithm of the relaxation time on the reciprocal of the temperature logτ ~ 1/T, consists of two parts and the value of the static dielectric permeability ε∞ is non-additive. To explain these results, it is assumed that clusters are formed in this system, the same as in the pure components.

This article discusses a new method for synthesizing diaryl disulfides and arylthio acetic acids using thioglycolic acid and copper catalysts. Traditional methods for synthesizing these compounds can be challenging, but this new method offers a more accessible approach. The article provides optimized reaction conditions and explores the substrate scope of the method, demonstrating its applicability to a variety of aryl iodides. The synthesized compounds can be used as intermediates for the synthesis of asymmetric sulfides. Overall, this method offers a cost-effective and readily available solution for the synthesis of these important compounds. [Extracted from the article]

This article discusses the importance of developing strategies to prevent and treat infections caused by the opportunistic bacterium Acinetobacter baumannii (A. baumannii), which is responsible for various hospital-acquired infections. The article suggests that vaccination or immunotherapy could be a potential alternative strategy to combat A. baumannii infections. The focus of the study is on the chemical synthesis of the octasaccharide repeating unit of the capsular polysaccharide (CPS) K55 of A. baumannii BAL_204 strain, which could be used for the development of glycoconjugate vaccine candidates. [Extracted from the article]

Comprehensive Summary: A metal‐free, green, and sustainable functionalization of unactivated alkyl sp3 C—H bonds is reported using iodine(III) as a feasible dehydrogenation agent under visible light or KBr, and alkyl chlorides, bromides, alcohols, and ketones could be constructed by addition of different coupling reagents. Cheap and safe iodobenzene diacetate was used to form a radical to activate the alkyl sp3 C—H bond in a highly efficient manner, which can construct different alkylation products by adding corresponding coupling reagents. [ABSTRACT FROM AUTHOR]

Continuous flow chemistry has become the method of choice for the synthesis of toxic and explosive intermediates such as diazo reagents because they can be generated on demand and readily used, eliminating the need to handle hazardous materials. This inherent increase in safety makes it more feasible to use these reagents in day-to-day synthesis. Herein, we describe a continuous flow, metal-free, easy-to-use method for the preparation of semi-stabilized and unstabilized diazo reagents. The scope of the described continuous flow oxidation of hydrazones using a packed bed column with iodosylbenzene includes 13 semi-stabilized and 13 unstabilized diazo reagents in solution in dichloromethane while producing only 1 equivalent of water and iodobenzene as by-products. These otherwise difficult to access compounds are further reacted either in situ or at the reactor outlet to yield esters and ethers in good to excellent yields (47–96%). [ABSTRACT FROM AUTHOR]

Materials exhibiting room temperature phosphorescence (RTP) have recently emerged as a subject of significant interest. In this study, we successfully created inclusion crystals by introducing halobenzenes as guests into a host molecule combining benzophenone with naphthalene diimide. This approach led to the creation of fascinating fluorescence and RTP properties dependent on the guest molecules. Notably, crystals containing chlorobenzene showed cyan fluorescence, while those with iodobenzene displayed red RTP. This difference highlights the impact of the guest molecule on the luminescent properties, with the significant external heavy‐atom effect of iodobenzene playing a key role in promoting efficient intersystem crossing between the excited singlet and triplet states. Crystals with bromobenzene exhibited a unique blend of fluorescence and RTP, both from benzophenone and naphthalene diimide, highlighting the moderate heavy‐atom effect. These findings reveal composite materials with remarkably diverse and interesting optical characteristics. [ABSTRACT FROM AUTHOR]

The theoretical treatment of the quantum dynamics of the phenyl iodide photodissociation requires an accurate analytical potential energy surface (PES) model. This model must also account for spin–orbit (SO) coupling. This study is the first step to construct accurate SO coupled PESs, namely, for the C–I dissociation coordinate. The model is based on the Effective Relativistic Coupling by Asymptotic Representation (ERCAR) method developed over the past ten years. The SO-free Hamiltonian is represented in an asymptotic diabatic basis and then combined with an atomic effective relativistic coupling operator determined analytically. In contrast to the previously studied cases (HI, CH3I), the diabatic basis states are due to excitations in the phenyl fragment rather than the iodine atom. An accurate analytical model of the ab initio reference data is determined in two steps. The first step is a simple reference model describing the data qualitatively. This reference model is corrected through a trained artificial neural-network to achieve high accuracy. The SO-free and the fine structure states resulting from this ERCAR model are discussed extensively in the context of the photodissociation. [ABSTRACT FROM AUTHOR]

Achieving high‐performance in all‐small‐molecule organic solar cells (ASM‐OSCs) significantly relies on precise nanoscale phase separation through domain size manipulation in the active layer. Nonetheless, for ASM‐OSC systems, forging a clear connection between the tuning of domain size and the intricacies of phase separation proves to be a formidable challenge. This study investigates the intricate interplay between domain size adjustment and the creation of optimal phase separation morphology, crucial for ASM‐OSCs' performance. It is demonstrated that exceptional phase separation in ASM‐OSCs' active layer is achieved by meticulously controlling the continuity and uniformity of domains via re‐packing process. A series of halogen‐substituted solvents (Fluorobenzene, Chlorobenzene, Bromobenzene, and Iodobenzene) is adopted to tune the re‐packing kinetics, the ASM‐OSCs treated with CB exhibited an impressive 16.2% power conversion efficiency (PCE). The PCE enhancement can be attributed to the gradual crystallization process, promoting a smoothly interconnected and uniformly distributed domain size. This, in turn, leads to a favorable phase separation morphology, enhanced charge transfer, extended carrier lifetime, and consequently, reduced recombination of free charges. The findings emphasize the pivotal role of re‐packing kinetics in achieving optimal phase separation in ASM‐OSCs, offering valuable insights for designing high‐performance ASM‐OSCs fabrication strategies. [ABSTRACT FROM AUTHOR]

Di(p‐benzi)[40]decaphyrin(1.0.0.0.0.1.0.0.0.0) BF2 complex and tris(p‐benzi)[60]pentadecaphyrin(1.0.0.0.0.1.0.0.0.0.1.0.0.0.0) BF2 complex were synthesized by Suzuki‐Miyaura coupling of α,α'‐diborylated tetrapyrrole BF2‐complex with 1,4‐diiodobenzene. Bis‐BF2 complex was converted to bis‐PdII complex via its free base. Macrocycles bis‐BF2 and tris‐BF2 complex take Möbius topology but are nonaromatic, since the macrocyclic conjugation is disrupted by the locally aromatic 1,4‐phenylene units. In contrast, bis‐PdII complex is a weakly Hückel 38π‐aromatic macrocycle as evinced by its red‐shifted, enhanced, and structured Q‐like bands and a small electrochemical HOMO‐LUMO gap. Interestingly, one 1,4‐pheylene part of bis‐PdII complex takes a quinonoidal distorted structure and the other takes a usual benzene structure in a figure‐eight conformation with Hückel topology. [ABSTRACT FROM AUTHOR]

Objectives: To synthesize a novel series of 3-(Aryl/Heteroaryl)-5-Methyl-7-Phenyl [1,2,4]triazolo[4,3a]Pyrimidines (5a-i). Materials and Methods: Synthesis was carried out though the microwave assisted synthesis, Spectroscopic approaches such as IR, 1HNMR and MASS spectroscopy were used to characterize the produced substances. Antimicrobial screening was done by Cup Plate Method for the antibiotic zone determination and Minimum Inhibitory Concentration was determined by the tube dilution method. Experimental Work: The oxidation of substituted pyrimidinylhydrazones in dichloromethane with iodobenzene diacetate was used in the synthesis. Substituted pyrimidinylhydrazones was obtained by the condensation of 1-(1,4-dihydro-6-methyl-4-phenylpyrimidine-2-yl)-hydrazine containing a variety of aromatic/heteroaromatic aldehydes. 3-(Aryl/Heteroaryl)-5-Methy l-7-Phenyl-[1,2,4]triazolo[4,3a]Pyrimidines (5a-i) were investigated in vitro for antibacterial activity against gram-positive bacteria such as Bacillus subtilis and Staphylococcus aureus, as well as gram-negative bacteria such as Escherichia coli and Pseudomonas putida. Results: 3-(4-fluorophenyl)-5-Methyl-7-Phenyl-[1,2,4]Triazolo[4,3a]Pyrimidine (5a) and 3-(4-Nitrophenyl)-5-Methyl-7-Phenyl-[1,2,4]Triazolo[4,3a]Pyrimidine (5e) found effective when compared to known marketed drugs Streptomycin and Chloramphenicol as both compounds are having the substitution of most electronegative groups which shows strong interaction with targeted DNA Gyrase enzyme of the bacteria. Conclusion: Microwave found to be an eco-friendly method for cyclization of pyrimidinylhydrazone to triazolopyrimidine. This method was found to be clean, safe and operationally simple which give triazolopyrimidine products with high yield. [ABSTRACT FROM AUTHOR]

The article presents the results of a study of the temperature dependence of the dielectric constant ε' and the dielectric loss index ε" of the chlorobenzene-iodobenzene system at wavelengths λ = 6.32; 4.01; 3.21; 2.14; 1.18 and 0.75 V temperature range -40°++30°. The static dielectric constant was determined at a frequency of 7 MHz. The temperature dependence of the time of dielectric relaxation of molecules in the liquid state was determined. It was established that in the specified temperature-frequency range the dispersion region consists of two parts. Analysis of the temperature dependence of dielectric polarization relaxation in the system chlorobenzene-iodobenzene shows that the relaxation times of the components do not depend on their short-range order. It was also discovered that the rate graph showing the dependence of the logarithm of the relaxation time on the reciprocal of the temperature logt -1/T, consists of two parts and the value of the static dielectric permeability ε∞ is non-additive. To explain these results, it is assumed that clusters are formed in this system, the same as in the pure components. [ABSTRACT FROM AUTHOR]

The reactivity of hexamethylcyclotrisiloxane (D3) towards BeCl2, BeBr2, BeI2 and [Be3Ph6]3 was investigated. While BeCl2 only showed unselective reactivity, BeBr2, BeI2 and [Be3Ph6] cleanly react to the trinuclear complexes [Be3Br2(OSiMe2Br)4], [Be3I2(OSiMe2I)4] and [Be3Ph2(OSiMe2Ph)4]. These unprecedented bromide, iodide and phenyl transfer reactions from a group II metal onto silicon offer a versatile access to previously unknown diorgano bromo and iodo silanolates. [ABSTRACT FROM AUTHOR]

Catalysts are essential materials in biotechnology, medicine, industry, and chemistry. On the other hand, recycling and using waste materials is important in economic efficiency and green chemistry. Thus, biochar was prepared from the stem and roots of the Spear Thistle to recover waste. After magnetizing the biochar, its surface was modified with polyvinyl imidazole. Finally, this modified biochar was decorated with Pd nanoparticles and used as a selective and recyclable nanocatalyst in the hydrogenation of nitroarenes and the Sonogashira reaction. The structure of this organic–inorganic nanocatalyst has been characterized by FESEM-EDS, XRD, FT-IR, TEM, and VSM techniques. In the hydrogenation reaction with the amount of 30 mg of nanocatalyst, the temperature of 50 °C in the water solvent, the reaction efficiency reached 99% for 30 min. In addition, under optimal conditions for the Sonogashira reaction: 1.0 mmol iodobenzene, 1.2 mmol phenylacetylene, 20 mg MBC-PVIm/Pd, 2 mmol K2CO3 in H2O at 50 C for 15 min, the reaction efficiency reached 95%. The recyclability of magnetic nanocatalysts was investigated and recognized this nanocatalyst can be used several times without notable loss of its activity. [ABSTRACT FROM AUTHOR]

Two series of binary halogen-bonded co-crystals involving perfluorinated di- and triiodobenzene (1,2-ditfb, 1,4-ditfb and 1,3,5-titfb) and 1,3-azulenedicarboxaldehyde (azdicho) 1 and 1,3-bis(4-pyridyl)azulene (azbbpy) 2 are reported. The crystal structures of the six new co-crystals show primarily O⋯I or N⋯I interactions, and the subsidiary weak C–H⋯F and π–π interactions of the aromatic units. Because the halogen-bond acceptors contain different heteroatoms and length size, the supramolecular recognition in the co-crystal is quite different. Besides novel structural features formed via halogen-bonding interactions, our results showed that the azulene moiety plays a unique organizing role in the formation and stabilization of supramolecular aggregates through π–π stacking interactions. These non-covalent interactions are investigated by theoretical studies through Hirshfeld surface analysis and DFT calculations followed by topological analysis of the electron density distribution within the QTAIM approach. The co-crystals were also investigated in solution by NMR spectroscopy through 19F-NMR and 1H,15N-HMBC experiments. [ABSTRACT FROM AUTHOR]

Two new ferrocene based molecules S,S′‐bis(4‐aminophenyl)ferrocene‐1,1'‐bis(carbothioate) (I) and S,S′‐bis(3‐aminophenyl)ferrocene‐1,1'‐bis(carbothioate) (II) have been synthesized via a thioester linkage. The prepared compounds have been successfully applied as ligands for the CuI catalyzed Sonogashira coupling reaction. The ligands are highly effective for the Csp2−Csp coupling between alkyne and iodobenzene and bromobenzene. Corresponding 1,2‐disubstituted alkynes could be synthesized from both aryl and alkyl alkynes in high yield by using catalytic amount of CuI in presence of bis(3‐aminophenyl)ferrocene derivative in dioxane at 50 °C. [ABSTRACT FROM AUTHOR]

This article discusses the development of a new method for synthesizing tetrasubstituted pyrroles, which are important in the pharmaceutical industry. The method combines three different components in one step, resulting in a more efficient and selective process with less waste. The researchers used readily available starting materials and performed the reaction without the need for a catalyst or solvent. The optimized conditions produced high yields of the desired product. The method was found to be environmentally friendly and the reaction mechanism involves the formation of new bonds. [Extracted from the article]

[Display omitted] • Two fluorinated and one non–fluorinated complex of the type [(NHC)Ni(Cp)(Br)] were synthesized and characterized. • The non–fluorinated complex showed higher catalytic activity than the fluorinated ones in the C–S cross–coupling reaction. • The catalytic reaction mechanism was studied by theoretical calculations. • Strong nucleophilic substrates quenched the C–S cross–coupling by forming a stable intermediate complex. The catalytic activities of three Ni(II) complexes with fluorinated and non–fluorinated N–heterocyclic carbene (NHC) ligands were evaluated in the C–S cross–coupling reaction between iodobenzene and thiophenol. The complexes with fluorinated–NHC ligands exhibited lower catalytic activities compared to the non–fluorinated derivative. This can be attributed to the lower electron–donating character of the fluorinated ligands in comparison to the non–fluorinated ligand. Complex 3–Ni was tested towards different substrates, achieving moderate to good conversions. Additionally, the reaction mechanism of the C–S cross–coupling using two substrates, tert–butylthiol and 2,4–dichlorobenzenethiol, was determined. Tert–butylthiol produced a stable intermediate that inhibited the last step of the reaction mechanism (reductive elimination). On the other hand, 2,4–dichlorobenzenethiol formed a less stable intermediate, favoring the reductive elimination. This observation aligns with the lower yield observed when using tert–butylthiol compared to 2,4–dichlorobenzenethiol (20% vs 99%). [ABSTRACT FROM AUTHOR]

Herein, we investigated the α-acetoxylation of ketones through various experiments. These include screening of reaction conditions, analysis of reactivity and selectivity over diverse ketones, kinetic study of the reaction of monoacetoxylation and diacetoxylation, density functional theory calculations for estimating the energy and structure, and analysis of natural bond orbitals. Based on the reaction products of the study, the pseudo first-order model is determined as the best model for the reaction, and the identification of the reaction intermediates indicates that iodonium is an essential intermediate in the reaction. Additionally, kinetic studies and theoretical calculations reveal that the reaction may utilize a different mechanism depending on the ketone structure; in this case, however, we focused on the α-acetoxylation of 4-tert-butylcyclohexanone. Based on these findings, we propose a reaction mechanism and the corresponding behavior description for iodine(III) in α-acetoxylation reactions. [ABSTRACT FROM AUTHOR]

Syndiotactic polystyrene (sPS) incorporates low‐mass guest molecules to form a co‐crystalline structure, the δ‐phase, in which the guest molecules are confined within a nanosized space. Under such spatial constraints, what factors determine the dynamics of the guest molecules? This is an interesting question and needs to be clarified toward the functionalization of sPS/functional guest systems. In this study, the size effect of the guest molecules and use monosubstituted halobenzenes (fluorobenzene, chlorobenzene, bromobenzene, and iodobenzene) to systematically change the molecular size is focussed. Since halobenzene has a large electric dipole moment, dielectric relaxation measurements can effectively detect its molecular motion. This study aims to identify the guest dynamics in the δ‐phase by dielectric relaxation measurement and examines the molecular length dependence of the rotational relaxation times and their activation energies. [ABSTRACT FROM AUTHOR]

With the irradiation of visible light, α‐heteroarylation of aliphatic alcohol was selectively achieved under gentle conditions in the present of iodobenzene dichloride. The Minisci‐type cross‐dehydrogenative coupling reaction was performed in the absence of metal and acid. Readily available primary alcohols and electron‐withdrawing heteroarenes can be applied smoothly. Mechanism studies indicated that the PhICl radical and chlorine radical formed from iodobenzene dichloride were responsible for the selective hydrogen atom abstraction of alcohols. [ABSTRACT FROM AUTHOR]

Active layer morphology is critical to determine the photovoltaic performance of organic solar cells (OSCs), and additive‐assisted morphology optimization is one of the most widely used strategies to fine tune the donor–acceptor network in the active layer. However, the postprocessing procedures and additive residues require additional efforts to maintain the device performance. Herein, a low‐cost, simple structural design and volatile solid additive 2,5‐diiodothiophene is demonstrated to effectively optimize the active layer morphology and prompt the photoelectric conversion efficiency (PCE) of OSCs without any post‐treatment, outperforming the devices fabricated with the prototypical volatile additive 1,4‐diiodobenzene. The 2,5‐diiodothiophene (DIT)‐optimized PM6:Y6 binary OSCs obtain a PCE of 17.48%, accompanied with reduced trap‐assisted charge recombination and balanced charge carrier mobility. In addition, we notice that the bromide and chlorine analogues of DIT can enhance the device performance to a certain extent as well. The findings suggest that the post‐treatment‐free nature of the thiophene‐based processing additives are promising candidates for tuning the active layer morphology, providing simple processability for large‐scale fabrication of OSCs. [ABSTRACT FROM AUTHOR]

Commercially available copper and copper (II) oxide nanoparticles (CuNPs and CuO NPs) were characterized using TEM and electronography methods to elucidate their true average size and composition. The catalytic amine arylation using unsupported copper nanoparticles differing in their size and copper oxidation state was investigated. The reaction of the model iodobenzene with n-octylamine was shown to be successfully catalyzed by CuNPs of average size 25 and 10/80 nm in the presence of the ligands such as 2-isobutyrylcyclohexanone (L1) and rac-1,1′-bi-2-naphthol (BINOL, L2), giving high yields (up to 95%) of the target N-octylaniline. CuO in bulk and nano forms was shown to be almost equally efficient in this process. Studies on the Cu-catalyzed amination of substituted iodobenzenes and 2-iodopyridine, as well as the arylation of different aliphatic amines and NH-heterocycles, verified that CuNPs (25 or 10/80 nm) with L1 and L2 are the most versatile and efficient nanocatalysts for a variety of substrates. Investigation of copper leaching under different conditions was carried out. [ABSTRACT FROM AUTHOR]

Copper-containing minerals are among the most abundant minerals on Earth. They play a fundamental role in our economy and, as presented in prebiotic studies, in the origin of life. Over 700 copper-containing minerals are present in nature with well-defined structure and formula. By utilizing the catalytic effect of such minerals, highly economical and green methods can be developed. One of such methods is presented in this study in copper mineral-catalyzed Goldberg arylation reactions of amides. A total of seven readily available minerals were tested in the reaction of iodobenzene with pyrrolidin-2-one with chrysocolla [(Cu,Al)2H2Si2O5(OH)4·n H2O] and malachite [Cu2(CO3)(OH)2] being the best applicable ones. After optimization, a wide variety of arylated amide derivatives were synthesized utilizing the catalytical effect of the above-mentioned minerals. The procedure proved to be feasible regardless of the origin of the catalyst making this method even more attractive. [ABSTRACT FROM AUTHOR]

Besides the most common form of aromaticity involving a π‐ring, hexaiodobenzene and hexakis(phenylselenyl)benzene dications also present σ‐aromaticity in the outer ring formed by the main group substituents. These two compounds are considered σ‐ and π‐double aromatic, and their characterization is of special interest to the fields of organic and structural chemistry. In this work, we decided to explore the double aromaticity in substituted tropylium cations for three reasons: (i) the seven neutral halogen substituents of the tropylium cations will, without oxidation, lead to 14 σ‐electrons (a 4n + 2 Hückel number); (ii) tropylium cations are highly stable and can be easily generated experimentally; and (iii) whereas in substituted benzenes the distances between substituents in the optimized structures or X‐ray crystals are too large to allow strong σ‐aromaticity, these distances are expected to be shorter in substituted tropylium cations. Yet, instead of the expected σ‐aromaticity, we found that the most stable geometries are highly puckered, meaning that delocalization in both π‐ and σ‐systems is lost. Our results, which include also the tropylium anion and trication in the singlet and triplet state, show that there is a need to open a lone pair hole by oxidation to generate σ‐aromaticity. Among the systems studied, only triplet C7Br7+3 with an internal Hückel aromatic tropylium ring and an external incipient Baird aromatic Br7 ring shows double π‐ and σ‐aromaticity. This result, however, is functional‐dependent and reveals that 3C7Br73+ is at the borderline for onset of double aromaticity. [ABSTRACT FROM AUTHOR]

In this research, ethyl levulinate, methyl levulinate, and 2-methyltetrahydrofuran as bio-derived hemicellulose-based solvents were applied as green alternatives in palladium-catalyzed aminocarbonylation reactions. Iodobenzene and morpholine were used in optimization reactions under different conditions, such as temperatures, pressures, and ligands. It was shown that the XantPhos ligand had a great influence on conversion (98%) and chemoselectivity (100% carboxamide), compared with the monodentate PPh3. Following this study, the optimized conditions were used to extend the scope of substrates with nineteen candidates (various para-, ortho-, and meta-substituted iodobenzene derivatives and iodo-heteroarenes), as well as eight different amine nucleophiles. [ABSTRACT FROM AUTHOR]

C−H bond activation has surfaced as a transformative toolbox for the efficient assembly of biologically important molecules. However, despite of major advances in palladium, rhodium and silver catalysis, yet palladium(II)‐ catalyzed, iodobenzene diacetate (PIDA) mediated C−H bond activation in azole skeleton has deluged with interesting wining outcome. Concentrating on that we herein report on the involvement of 4‐functionalized 1,4‐dihydropyridines (R‐DHPs) as the representative surrogates of benzoyl, pivalyl and ethoxycarbonyl groups and in presence of PIDA it releases appropriate functional radical (following single electron transfer oxidation of R‐DHPs under thermal condition)to become the part of ortho‐ functionalized azoles via Pd(II) catalysis. In case of cyanation reaction, malononitrile has served the key source of nitrile functionality by undergoing oxidative C−CN bond cleavage in presence of PIDA and with the help of Pd(II) catalyst it offers ortho‐cyanated azoles. Additionally, the selective formation of C‐3 benzoyl and ester functionalized indazole derivatives in absence of Pd(II)‐catalyst and the unprecedented formation of homo‐coupling products between two identical 2H‐indazoles are also notable outcome of present strategic access. Overall this protocol operates under mild condition, tolerates a wide range of structural moieties and gives versatile azole derivatives in high efficiency. The antioxidant properties of the synthesized 2‐thiophenyl benzoyl selenazole and isoselenazole are further evaluated using a chemically defined method. The Copper‐ascorbate (Cu−As) was utilized as an oxidative stress generator. Out of screened azoles, the 2‐benzoyl isoselenazole compound (3 i) displays magnificent antioxidant property as compared to the 2‐thiophenyl benzoyl selenazole (3 g). [ABSTRACT FROM AUTHOR]

Metal-free direct C–H functionalization reactions are a promising approach to convert hydrocarbon feedstock into value-added molecules. Diacetoxyl iodobenzene (DIB) is a benchtop stable hypervalent iodine compound that is frequently used as a non-metal oxidant in C–H functionalization. However, DIB has a relatively low reactivity and an acid promoter is usually required to achieve satisfactory performance. Herein, we report the use of a DIB/BBr3 protocol for metal-free C(sp2)–H activation/cross-coupling of arenes. [ABSTRACT FROM AUTHOR]

A Minisci-type reaction catalyzed by iodobenzene is disclosed here for the first time. The heteroarylation of unprotected aliphatic alcohols proceeds via alkoxy radical-induced homolytic cleavage of C–H and C–C bonds under photochemical conditions. The use of m-CPBA as the oxidant allows the oxidation of iodobenzene to a hypervalent iodine species, driving the catalytic cycle. The method features mild reaction conditions, broad scope of heteroarenes and alcohols, and scaled up preparations. This approach provides a notable supplement to iodobenzene-catalyzed ionic reactions, and opens up a new avenue for its application in radical chemistry.

The photodissociation dynamics of 1,4-diiodobenzene is investigated using ultrafast time-resolved photoelectron spectroscopy. Following excitation by laser pulses at 271 nm, the excited-state dynamics is probed by resonance-enhanced multiphoton ionization with 405 nm probe pulses. A progression of Rydberg states, which come into resonance sequentially, provide a fingerprint of the dissociation dynamics of the molecule. The initial excitation decays with a lifetime of 33 ± 4 fs, in good agreement with a previous study. The spectrum is interpreted by reference to ab initio calculations at the CASPT2(18,14) level, including spin-orbit coupling. We propose that both the 5B1 and 6B1 states are excited initially, and based on the calculations, we identify diabatic spin-orbit coupled states corresponding to the main dissociation pathways. [ABSTRACT FROM AUTHOR]

Dimagnesium(I) complexes [{(Arnacnac)Mg}2], where Arnacnac=HC(MeCNAr)2, Ar=Dip=2,6‐iPr2−C6H3, Ar=Dep=2,6‐Et2−C6H3, Ar=Mes=2,4,6‐Me3−C6H2, react with iodoarenes in oxidative addition reactions. With iodobenzene, magnesium phenyl and magnesium iodide complex fragments were obtained, and from a reaction with 4‐iodo‐1,2,3,5‐tetramethylpyrazolium iodide, [MePZI]I, the pyrazol‐4‐ylidene complex [(Dipnacnac)MgI(MePZ)] was structurally characterised, alongside other products. The isomeric imidazol‐2‐ylidene complex [(Dipnacnac)MgI(MeNHC)], where MeNHC is 1,3,4,5‐tetramethylimidazol‐2‐ylidene, was prepared and characterised. X‐ray crystal structure determinations and DFT computational studies have been carried out to compare the related complexes. The results show that the MePZ ligand is higher in energy and more nucleophilic than its more common isomeric MeNHC carbene. [ABSTRACT FROM AUTHOR]

The 2‐hydrazinyl‐1,3‐benzothiazole derivatives are precursors for synthesis of several compounds of technological interest, including the Bt−NH−N=CHR1 (R1=alkyl, aryl, heteroaryl), derivatives. Usually when Bt−NH−NH2 is allowed to react with a benzenesulfonyl chloride the substitution is observed in the terminal nitrogen of the arenehydrazine unit, but when 4‐iodophenyl sulfonyl chloride (4‐IC6H4SO2Cl) was used, the product isolated was the title compound as confirmed by Rx‐analysis. Determination of the crystal structure revealed that the definition of the arrangement was driven by N−H⋅⋅⋅π, C−I⋅⋅⋅π and S2−O21⋅⋅⋅π interactions instead of the classic O⋅⋅⋅H−N hydrogen bonds. The interactions were confirmed by HS analysis. Interaction energy calculations showed that the π interactions‐based motifs play an important role in the supramolecular arrangement, contributing about 60 % to the total energy of the lattice. DFT calculations showed that the energy of the C−I⋅⋅⋅π dimer is complemented with contributions of π⋅⋅⋅π stacking and N−H⋅⋅⋅π interaction between the primary amine and the thiazole aromatic ring. [ABSTRACT FROM AUTHOR]

In this study, we considered the reaction of (E)-1-[(2-phenylhydrazono)methyl]naphthalen-2-ol with iodobenzene diacetate in dichloromethane-produced novel 3-phenyl-3H-naphtho[1,2-e][1,2,3]oxadiazine in 11% yield. By analogy to previously published work, we suggested that the reaction proceeds via the intermediacy of an o-naphthoquinone azomethide that undergoes conjugated 6π-electrocylization to produce the product. 1D, 2D NMR, HRMS, IR, and UV-VIS spectra provided information that supported the structure of the product. [ABSTRACT FROM AUTHOR]

Surface‐plasmon‐mediated phenylacetylide intermediate transfer from the Cu to the Pd surface affords a novel mechanism for transmetalation, enabling wavelength‐tunable cross‐coupling and homo‐coupling reaction pathway control. C−C bond forming Sonogashira coupling and Glaser coupling reactions in O2 atmosphere are efficiently driven by visible light over heterogeneous Cu and Pd nanoparticles as a mixed catalyst without base or other additives. The reaction pathway can be controlled by switching the excitation wavelength. Shorter wavelengths (400–500 nm) give the Glaser homo‐coupling diyne, whereas longer wavelength irradiation (500–940 nm) significantly increases the degree of cross‐coupling Sonogashira coupling products. The ratio of the activated intermediates of alkyne to the iodobenzene is wavelength dependent and this regulates transmetalation. This wavelength‐tunable reaction pathway is a novel way to optimize the product selectivity in important organic syntheses. [ABSTRACT FROM AUTHOR]

A protocol for synthesizing symmetrical thioethers by using a cheap organosulfur reagent (tetramethylthiuram monosulfide: TMTM) was developed. Both iodobenzenes and phenylboronic acids react well with TMTM, giving the target products with good to excellent yields. This method features simple performance, wide functional group tolerance, and good to excellent yields, showing a potential application value for the synthesis of drug molecules. [ABSTRACT FROM AUTHOR]

[Display omitted] • The halogenation of imidazoheterocycles including iodine, bromine and chlorine imidazoheterocycles could perform in very simple and mild conditions. • This transformation features with short reaction time, ambient temperature, facile operation, good functional group tolerance and good yeilds. An efficient and environment-friendly method for the synthesis of 3-haloimidazopyridine derivatives has developed by the halogenation of imidazoheterocycles with Bu 4 NX (X = Cl, Br, and I) using iodobenzene diacetate as oxidant in ethanol. This protocol features with short reaction time for bromination and iodination, ambient temperature, facile operation, good functional group tolerance and good yeilds. [ABSTRACT FROM AUTHOR]

[Display omitted] • Experimental viscosities for C 6 H 5 I + n -C n at (288.15–308.15) K are reported. • Correlation equations and Bloomfield-Dewan's model have been applied. • The systems studied theoretically are of the type aromatic compound, or C 6 H 12 + n -C n. • A close relationship exists between U V m E (n) and Δ η (n). • The free volume theory describes well η of the solutions. • DISQUAC is used to calculate the residual Gibbs energy in Bloomfield-Dewan's model. Kinematic viscosities were measured for iodobenzene + n -alkane mixtures at (288.15–308.15) K and atmospheric pressure. The corresponding dynamic viscosities (η) were also determined using density data previously obtained in our laboratory. This set of data was employed to calculate Δ η (deviations in absolute viscosity) and quantities of viscous flow. In addition, the correlation equations: McAllister, Grunberg-Nissan, Fang-He, and the Bloomfield-Dewan's model were applied to the systems: iodobenzene, or 1-chloronaphthalene, or 1,2,4-trichlorobenzene, or methyl benzoate or benzene or cyclohexane + n -alkane. It is remarkable that, within the Bloomfield-Dewan's model, residual Gibbs energies were calculated using DISQUAC with interaction parameters available in the literature. From the dependence of U V m E (isochoric molar excess internal energy) and Δ η with n (the number of C atoms of the n -alkane), it is shown that the loss of fluidization of mixtures containing iodobenzene, 1,2,4-trichlorobenzene, or 1-chloronaphthalene when n increases can be ascribed to a decrease, upon mixing, of the number of broken interactions between like molecules. The breaking of correlations of molecular orientations characteristic of longer n -alkanes may explain the decreased negative Δ η values of benzene mixtures with n = 14,16. The replacement, in this type of systems, of benzene by cyclohexane, leads to increased positive Δ η values, probably due to the different shape of cyclohexane. On the other hand, binary mixtures formed by an aromatic polar compound mentioned above and a short n -alkane show large structural effects and large negative Δ η values. From the application of the models, it seems that dispersive interactions are dominant and that size effects are not relevant on η values. The free volume model provides good results for most of the systems considered, since deviations are less than 6% for 20 mixtures from the 29 solutions under study, and only 4 systems show deviations higher than 10%, with a maximum deviation of 15%. Results improve when, within the Bloomfield-Dewan's theory, the contribution to η of the absolute reaction rate model is also considered. [ABSTRACT FROM AUTHOR]

Benzodiazepines are essential structural motifs commonly found in biologically active compounds and pharmaceutical agents. General and step-economical methods for the direct synthesis of benzodiazepines from simple and easily accessible starting materials remain a continuous challenge for synthetic chemists. Herein, a highly efficient synthetic method for benzodiazepine has been reported, which involves a ppm-level Pd-catalysed carbonylative coupling of iodobenzene with terminal alkynes to afford 1,3-ynones as key intermediates and a subsequent Cp2TiCl2/m-phthalic acid/ethanol-catalysed cyclocondensation in one-pot conditions. The new approach proceeds with a broad substrate scope under mild reaction conditions, providing benzo[b][1,4]diazepines in up to 90% yield. [ABSTRACT FROM AUTHOR]

Anionic, metal‐centered nucleophiles are emerging compounds with unique reactivities. Here, we describe the isolation and full characterization of the first tetraamido tin(II) dianion, its behavior as ligand towards transition metals, and its reactivity as a tin‐centered nucleophile. Experimental values such as the Tolman electronic parameter (TEP) and computations attest tin‐located σ‐donor ability exceeding that of carbenes or electron‐rich phosphines. Against transition metals, the stannate(II) can act as η1‐ or η5‐type ligand. With aldehydes, it reacts by hydride substitution to give valuable acyl stannates. The reductive dehalogenation of iodobenzene indicates facile redox pathways mediated by halogen bond interaction. Calix[4]pyrrolato stannate(II) represents the first example of this macrocyclic ligand in low‐valent p‐block element chemistry. [ABSTRACT FROM AUTHOR]

Ultrafast x-ray photoelectron diffraction (UXPD) for free molecules has a promising potential to probe the local structures of the molecules in an element-specific fashion. Our UXPD scheme consists of three steps: (1) near-infrared laser (NIR) with ns pulse duration aligns sample molecules, (2) ultra-violet laser with fs pulse duration pumps the aligned molecules, and (3) soft x-ray free-electron laser (SXFEL) with fs pulse duration probes the molecules by measuring x-ray photoelectron diffraction (XPD) profiles. Employing steps of (1) and (3), we have measured I 3d XPD profiles from ground state iodobenzene aligned by the NIR laser with the SXFEL. Then, we have intensively calculated I 3d XPD profiles with density functional theory, taking degrees of alignments of the molecules into account, to extract a distance between C and I atoms in iodobenzene from the experimental I 3d XPD profiles. Although we have failed to determine the distance from the comparison between the experimental and theoretical results, we have succeeded in concluding that the degeneracies of the initial state eliminate the sensitivity on molecular structure in the I 3d XPD profiles. Thus, the observation of fine structures in the XPD profiles could be expected, if a nondegenerate molecular orbital is selected for a probe of UXPD. Finally, we have summarized our criteria to perform UXPD successfully: (1) to use SXFEL, (2) to prepare sample molecules with the degree of alignment higher than 0.8, and (3) to select a photoemission process from a nondegenerate inner-shell orbital of sample molecules. [ABSTRACT FROM AUTHOR]

The current work assessed the degradation degree and the degradation products derived from norfloxacin (NOR) and gentamicin (GEN) using iodosylbenzene and iodobenzene diacetate, in the presence of manganese porphyrin as catalysts. Better results for NOR degradation (> 80%) were obtained when more hydrophobic porphyrins were employed. β-brominated manganese porphyrins showed a lower GEN degradation (~ 25%) than the non-brominated ones (~ 35%), probably due to their steric hindrance. In any case, complete mineralization was achieved neither for NOR nor for GEN, and the assignment of the generated products, complemented by the study of their toxicity, was an important step performed. From the obtained results, no correlation was found between the number of identified products and the reported toxicity value (rSpearman,NOR = 0.006; p value = 0.986 and rSpearman,GEN = − 0,198; p value = 0.583), which reinforces the idea of synergism and antagonistic phenomena. The higher degradation degree could have led to products of lower steric hindrance and easier penetration into the A. fischeri cells, which subsequently led to an increase in toxicity for these experiments. In most cases, the products presented higher toxicity than the original compound, which raises a concern about their occurrence in environmental matrices. [ABSTRACT FROM AUTHOR]

A bulky 1,4-di-iodobenzene having four adjacent para-tBu-C6H4 group (Ar′) substituents (1) was used to prepare the di-hypervalent iodine compound 1,4-[I(OAc)2]2-2,3,5,6-Ar′4-C6 (2). Despite the steric encumbrance of the iodine center by the flanking aryl substituents, compound 2 undergoes ready cyclization under mild conditions (excess CF3COOH at 55 °C, 30 min) to afford a dicyclic di-iodonium di-triflate salt 3. The single crystal structures of compounds 2 and 3 were examined and compared to the formerly characterized precursor 1. The para-tert-butyl groups on these compounds also render the compounds more soluble than multifunctional hypervalent iodine (HVI) compounds. HVI compounds having multiple iodine(III) centers are increasingly of interest for applications as recyclable reagents, materials precursors, and as Lewis acids. [ABSTRACT FROM AUTHOR]

Organo hypervalent iodine reagents are nowadays more attractive and versatile reagents for various chemical transformations in synthetic organic chemistry. These reagents are milder and having similar reactivity compared with toxic heavy metal reagents. Organo hypervalent iodine (λ3) reagents are successfully utilized to prepare synthetically and biologically important heterocycles. Hydroxy(tosyloxy)iodobenzene (HTIB) also acknowledged as Koser's reagent uses as an environmentally sustainable alternative to toxic heavy metals for the numerous and valuable organic transformations. The goal of this review is to highlight the recent advancements of the HTIB especially in the construction of heterocycles with various substitution patterns in a well‐organized form via tosyloxylation of ketones and oxidative cyclization methodology. This review compiles the up‐to‐date synthetic advancements of HTIB in the field of heterocycles. [ABSTRACT FROM AUTHOR]

The iodobenzene-catalyzed oxidative cyclization of a δ-alkynyl β-ketoester has been investigated by density functional theory (DFT) calculations at the CPCM(acetonitrile)/B3LYP/6-311++G(d,p)//B3LYP/SDD(I) levels. Three different mechanisms were considered for this process, and of the three, activation of the alkyne by a hypervalent iodine species followed by cyclization was found to be the most likely pathway based upon our computational results. [ABSTRACT FROM AUTHOR]

Oxidative addition represents a critical elementary step in myriad catalytic transformations. Here, the importance of thoughtful ligand design cannot be overstated. In this work, we report the intermolecular activation of iodobenzene (PhI) at a coordinatively saturated 18‐electron [Ni0(diphosphine)2] complex bearing a Lewis acidic secondary coordination sphere. Whereas alkyl‐substituted diphosphine complexes of Group 10 are known to be unreactive in such reactions, we show that [Ni0(P2BCy4)2] (P2BCy4=1,2‐bis(di(3‐dicyclohexylboraneyl)‐propylphosphino)ethane) is competent for room‐temperature PhI cleavage to give [NiII(P2BCy4)(Ph)(I)]. This difference in oxidative addition reactivity has been scrutinized computationally – an outcome that is borne out in ring‐opening to provide the reactive precursor – for [Ni0(P2BCy4)2], a "boron‐trapped" 16‐electron κ1‐diphosphine Ni(0) complex. Moreover, formation of [NiII(P2BCy4)(Ph)(I)] is inherent to the P2BCy4 secondary coordination sphere: treatment of the Lewis adduct, [Ni0(P2BCy4)2(DMAP)8] with PhI provides [NiII(P2BCy4)2(DMAP)8(I)]I via iodine‐atom abstraction and not a [NiII(Ph)(I)(diphosphine)] compound – an unusual secondary sphere effect. Finally, the reactivity of [Ni0(P2BCy4)2] with 4‐iodopyridine was surveyed, which resulted in a pyridyl‐borane linked oligomer. The implications of these outcomes are discussed in the context of designing strongly donating, and yet labile diphosphine ligands for use in a critical bond activation step relevant to catalysis. [ABSTRACT FROM AUTHOR]