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The use of sulfonium salts in organic synthesis has experienced a dramatic increase during the last years that can arguably be attributed to three main factors; the development of more direct and efficient synthetic methods that make easily available sulfonium reagents of a wide structural variety, their intrinsic thermal stability, which facilitates their structural modification, handling and purification even on large scale, and the recognition that their reactivity resembles that of hypervalent iodine compounds and therefore, they can be used as replacement of such reagents for most of their uses. This renewed interest has led to the improvement of already existing reactions, as well as to the discovery of unprecedented transformations; in particular, by the implementation of photocatalytic protocols. This review aims to summarize the most recent advancements on the area focusing on the work published during and after 2020. The scope of the methods developed will be highlighted and their limitations critically evaluated. [ABSTRACT FROM AUTHOR]

A convenient and selective method for the preparation of substituted iodoalkynes, iodoalkenes based on the interaction of propargylic compounds with iodine in the presence of readily available cadmium (II) acetate in some solvents was developed. The highest yields of iodoalkynes and iodoalkenes were recorded using DMSO as the solvent. An excess of the alkylpropargyl substrate unambiguously led to iodolkynes. By varying the reaction conditions using a twofold excess of iodine in DMSO, methanol or ethanol it was possible to achieve a one‐pot preparation of triiodoalkenes. The interaction of iodine with propargyl substrates could be represented in two ways: formation and further nucleophilic transformation of the iodonium complex under the influence of the acetate ion and generation of π‐coordinated species and elimination of acetic acid. [ABSTRACT FROM AUTHOR]

This mini review article provides an overview on the use of hypervalent iodine compounds (HICs) in carbohydrate synthesis, focusing on their chemistry and recent applications. HICs are similar to transition metals in their reactivity but have the added benefit of being environmentally benign, and are therefore commonly used as selective oxidants and eco‐friendly reagents in organic synthesis. Herein, we summarize various synthetic uses of hypervalent iodine reagents in reactions such as glycosylation, oxidations, functionalization, and C−C bond‐forming reactions. The goal of this review is to illustrate the advantages and versatility of using HICs as an environmentally sustainable alternative to heavy metals in carbohydrate chemistry. [ABSTRACT FROM AUTHOR]

Kinetics of the reactions of colored carbanions (reference nucleophiles) with S‐(trifluoromethyl)dibenzothiophenium ions (Umemoto's reagents) and hypervalent trifluoromethyl‐substituted iodine compounds (Togni's reagents) have been determined photometrically using stopped‐flow techniques. The second‐order rate constants k2(20 °C) for the reactions of Umemoto's sulfonium ions (generation I and II) with the reference nucleophiles in DMSO follow the correlation lg k2(20 °C)=sN(N+E) and can be used to determine the electrophilicity parameters E of these trifluoromethylating reagents. It is shown that the conditions reported for the reactions of Umemoto's generation I reagents with a variety of C‐nucleophiles are in line with the electrophilicity parameter E≈−13 determined for these reagents. Though Togni's hypervalent iodine‐based trifluoromethylation reagents do not follow this linear free energy relationship, the kinetics of their reactions with carbanions indicate that they cover the same reactivity range as Umemoto's generation I and II reagents. [ABSTRACT FROM AUTHOR]

Kainate receptors play a crucial role in mediating synaptic transmission within the central nervous system. However, the lack of selective pharmacological tool compounds for the GluK3 subunit represents a significant challenge in studying these receptors. Recently presented compound 1 stands out as a potent antagonist of GluK3 receptors, exhibiting nanomolar affinity at GluK3 receptors and strongly inhibiting glutamate‐induced currents at homomeric GluK1 and GluK3 receptors in HEK293 cells with Kb values of 65 and 39 nM, respectively. This study presents the synthesis of two potent GluK3‐preferring iodine derivatives of compound 1, serving as precursors for radiolabelling. Furthermore, we demonstrate the optimisation of dehalogenation conditions using hydrogen and deuterium, resulting in [2H]‐1, and demonstrate the efficient synthesis of the radioligand [3H]‐1 with a specific activity of 1.48 TBq/mmol (40.1 Ci/mmol). Radioligand binding studies conducted with [3H]‐1 as a radiotracer at GluK1, GluK2, and GluK3 receptors expressed in Sf9 and rat P2 membranes demonstrated its potential applicability for selectively studying native GluK3 receptors in the presence of GluK1 and 2‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA) receptor‐blocking ligands. [ABSTRACT FROM AUTHOR]

A Cu(I)‐catalyzed synthesis of α‐arylated sulfoxonium ylides has been achieved from mesitylene‐derived diaryliodonium salts and α‐carbonyl sulfoxonium ylides. The reaction is believed to proceed via an electrophilic Cu(III)‐aryl intermediate that can be trapped upon nucleophilic attack of the sulfoxonium ylide precursor. The reaction was tolerant to both α‐keto and α‐ester‐derived sulfoxonium ylides, to drug‐derived ylide motifs and to electronically‐diverse arenes, and enabled the direct synthesis of 32 α‐aryl‐sulfoxonium ylides in 42–85% yield. [ABSTRACT FROM AUTHOR]

Diazomethyl‐substituted iodine(III) compounds with electron‐withdrawing groups (EWG) connected to diazo methyl center were a type of donor‐acceptor diazo compounds with potential reaction abilities similar to ordinary diazo compounds. Although several diazomethyl‐substituted iodine(III) compounds were synthesized and used in the nucleophilic substitution reactions as early as 1994, the synthesis and application of new iodine(III) diazo compounds have only been reported to a certain extent in recent years. In the presence of rhodium catalyst, photocatalyst, or nucleophiles, diazomethyl‐substituted iodine(III) compounds can be converted into rhodium‐carbenes, diazomethyl radicals, ester radicals or nucleophilic intermediates, which can be used as key intermediates for the formation of chemical bonds. The aim of this review is to give an overview of diazomethyl‐substituted iodine(III) compounds in organic synthesis. [ABSTRACT FROM AUTHOR]

Microbial biofilms are a major hindrance in the wound healing process, prolonging the inflammatory response phase, thus making them a target in treatment. The aim of this study is to assess the antibacterial properties of commercially available wound dressings, of various material composition and antibacterial agents, towards multiple in vitro microbial and biofilm models. A variety of in vitro microbial and biofilm models were utilised to evaluate the ability of wound dressing materials to sequester microbes, prevent dissemination and manage bioburden. Sequestering and dissemination models were used to evaluate the ability of wound dressing materials to prevent the biofilm‐forming bacterium, Pseudomonas aeruginosa, from migrating through dressing materials over a 24–72 h challenge period. Additionally, Centre for Disease Control (CDC) Bioreactor and Drip Flow models were used to evaluate antibacterial killing efficacy towards established P. aeruginosa and Staphylococcus aureus biofilms using more challenging, wound‐like models. Controlled‐release iodine foam and silver‐impregnated carboxymethylcellulose (CMC) wound dressing materials demonstrated potent biofilm management properties in comparison to a methylene blue and gentian violet‐containing foam dressing. Both the iodine‐containing foam and silver‐impregnated CMC materials effectively prevented viable P. aeruginosa dissemination for up to 72 h. In addition, the controlled‐release iodine foam and silver‐impregnated CMC materials reduced P. aeruginosa bioburden in the Drip Flow model. The controlled‐release iodine foam demonstrated superiority in the CDC Bioreactor model, as both the silver‐ and iodine‐containing materials reduced S. aureus to the limit of detection, but P. aeruginosa growth was only completely reduced by controlled‐release iodine foam dressing materials. The data generated within the in vitro biofilm models supports the clinical data available in the public domain for the implementation of iodine foam dressings for effective biofilm management and control in wound care. [ABSTRACT FROM AUTHOR]

Hypervalent iodine compounds are described with perfluoroalkyl chains and S‐perfluoromethyl sulfoximines as ligands of the halogen. The influence of these groups on the stability of the cyclic structure is studied. The crucial role of the trifluoromethyl chain is clearly highlighted as an efficient ligand for the hypervalency. The structure and the reactivity of the new skeletons are discussed in detail. [ABSTRACT FROM AUTHOR]

Hypervalent iodine compounds have found broad application in modern organic chemistry as reagents and catalysts. Cyclic hypervalent iodine reagents based on the benziodoxole heterocyclic system have higher stability compared to their acyclic analogues, which makes possible the preparation and safe handling of the reagents with special ligands such as azido, cyano, and trifluoromethyl groups. Numerous iodine‐substituted benziodoxole derivatives have been prepared and utilized as reagents for transfer of the substituent on hypervalent iodine to organic substrate. Reactions of these reagents with organic substrates can be performed under metal‐free conditions, in the presence of transition metal catalysts, or using photocatalysts under photoirradiation conditions. In this review, we focus on the most recent synthetic applications of cyclic hypervalent iodine(III) reagents with the following ligands: N3, NHR, CN, CF3, SCF3, OR, OAc, ONO2, and C(=N2)CO2R. The review covers literature published mainly in the last 5 years. [ABSTRACT FROM AUTHOR]

The 3,4‐ethylenedioxy thiophene (EDOT)‐based conjugated microporous polymers (CMPs) were readily constructed via facile one‐step direct arylation polymerication of CH from simple EDOT as a linker and commercially available aryl bromides of different geometries as the knots, without preactivation of CH bonds of aromatic building blocks using organometallic reagents. In contrast to conventional coupling reactions, this synthesis strategy not only has atomic efficiency but also can use simple thiophene derivatives as building blocks for synthesizing thiophene‐based CMPs of different structures, which avoids the synthesis of complex thiophene derivatives and are important for applications, for example, fluorescent sensors. The resulting EDOT‐based CMPs were used to fluorescent sensing to 2,4‐dinitrophenol (DNP), I2, and p‐nitrophenol (p‐NP), with high optimal Stern‐Volmer quenching constants. [ABSTRACT FROM AUTHOR]

Hypervalent iodine reagents have the ability of inverting the polarity of functional groups bound to iodine, a reactivity known as umpolung. This reactivity makes hypervalent iodine compounds highly attractive for the creation of electrophilic synthons of known nucleophiles, resulting in novel synthetic disconnections and the formation of new Nu(nucleophile)−N bond. Electrophilic sources of nitrogen‐based groups have been known for many decades and are of great synthetic importance. Traditionally, these reagents are limited to few examples. With the use of hypervalent iodine, the transfer of a wide diversity of nitrogen sources became a possibility. This review compiles the latest reported examples of hypervalent iodine reagents capable of electrophilic transfer of nitrogen‐based groups. It showcases the preparation of such reagents, their synthetic utility, and reaction mechanisms involving these group transfer reagents. [ABSTRACT FROM AUTHOR]

We report an efficient radical‐mediated C−C coupling through photoredox‐catalyzed reactions of 4‐alkyl‐dihydropyridines (DHPs) and vinylbenziodoxol(on)es (VBX, VBO). This transition‐metal‐free and mild photocatalytic method has excellent functional group tolerance and affords vinylated products in good yields, with complete retention of the alkene configuration. The utility of the methodology is demonstrated by the diastereoselective synthesis of C‐vinyl glycosides. Preliminary mechanistic studies suggest that the C−C bond formation is stereospecific and proceeds through a concerted radical coupling transition state. [ABSTRACT FROM AUTHOR]

The aim of this feasibility study was to investigate the impact of inflammation management on wound pH, temperature, and bacterial burden, using the principles of TIME and Wound Bed Preparation. A quantitative non‐comparative, prospective, descriptive observational design. Following ethical approval, 26 participants with 27 wounds of varying aetiologies were observed twice weekly for 2 weeks. Wounds were treated with cleansing, repeated sharp debridement, and topical cadexomer iodine. Wound pH (pH indicator strips), temperature (infrared camera), bacterial burden (fluorescence imaging) and size (ruler method) was monitored at each visit. The mean age of all participants was 47 years (SD: 20.3 years), and 79% (n = 19) were male, and most wounds were acute (70%; n = 19) and included surgical and trauma wounds, the remaining (30%; n = 8) were chronic and included vascular ulcers and non‐healing surgical wounds. Mean wound duration was 53.88 days (SD: 64.49 days). Over the follow up period, pH values ranged from 6 to 8.7, temperature (centre spot) ranged from 28.4°C to 36.4°C and there was an average 39% reduction in wound size. Inflammation management had a positive effect on pH, temperature, bacterial burden, and wound size. This study demonstrated that it was feasible to practice inflammation management using a structured approach to enhance wound outcomes. [ABSTRACT FROM AUTHOR]

We report the synthesis of [6,7,5]‐tricyclic compounds containing an oxabicyclo [3.2.1] octane system from 1,6‐enyne carbonyl. We also synthesized [6,7,6]‐tricyclic compound from 1,7‐enyne carbonyl through Au‐catalyzed cyclization. The synthesis of oxacyclic compounds using iodine or oxygen is environmentally friendly cyclization methods. Oxacyclic compounds are useful for synthesizing various diterpene alkaloids. [ABSTRACT FROM AUTHOR]

The electrochemical intramolecular cross‐dehydrogenative C(sp2)−H/N−H coupling of α,β‐unsaturated hydrazones resulting in substituted pyrazoles has been discovered. The process is catalyzed by hypervalent iodine species generated in situ through anodic oxidation of aryl iodide in fluorinated alcohol media. The formation of hypervalent iodine compound and its key role in the construction of a new C−N bond was confirmed with CV and NMR experiments. A wide range of substituted pyrazoles were obtained in yields ranging from 46% to 88%. [ABSTRACT FROM AUTHOR]

Periodate, a platform oxidizer, can be electrochemically recycled in a self‐cleaning process. Electrosynthesis of periodate is well established at boron‐doped diamond (BDD) anodes. However, recovered iodate and other iodo species for recycling can contain traces of organic impurities from previous applications. For the first time, it was shown that the organic impurities do not hamper the electrochemical re‐oxidation of used periodate. In a hydroxyl‐mediated environment, the organic compounds form CO2 and H2O during the degradation process. This process is often referred to as "cold combustion" and provides orthogonal conditions to periodate synthesis. To demonstrate the strategy, different dyes, pharmaceutically active ingredients, and iodine compounds were added as model contaminations into the process of electrochemical periodate production. UV/Vis spectroscopy, NMR spectroscopy, and mass spectrometry (MS) were used to monitor the degradation of organic molecules, and liquid chromatography‐MS was used to control the purity of periodate. As a representative example, dimethyl 5‐iodoisophthalate (2 mm), was degraded in 90, 95, and 99 % while generating 0.042, 0.054, and 0.082 kilo equiv. of periodate, respectively. In addition, various organic iodo compounds could be fed into the periodate generation for upcycling such iodo‐containing waste, for example, contrast media. [ABSTRACT FROM AUTHOR]

New iodotriptycenes, including some chiral derivatives, have been synthesised, and their catalytic potential towards oxidative transformations has been investigated. The enantioselectivities observed in the products using chiral iodotriptycene catalysts are low, probably owing to the large distances between the coordinating groups and the iodine moieties in these compounds. [ABSTRACT FROM AUTHOR]

A remarkable growth in hypervalent iodine-mediated oxidative transformations as stoichiometric reagents as well as catalysts has been well-documented due to their excellent properties, such as mildness, easy handling, high selectivity, environmentally friendly nature, and high stability. This review aims at highlighting the asymmetric oxidative dearomatization reactions involving hypervalent iodine compounds. The present article summarizes asymmetric intraand intermolecular dearomatization reactions using chiral hypervalent iodine reagents/catalysts as well as hypervalent iodine-mediated dearomatization reactions followed by desymmetrization. [ABSTRACT FROM AUTHOR]

Hypervalent iodine compounds are powerful reagents for the development of novel transformations. As they exhibit low toxicity, high functional group tolerance, and stability in biocompatible media, they have been used for the functionalization of biomolecules. Herein, we report recent advances up to June 2021 in peptide and protein modification using hypervalent iodine reagents. Their use as group transfer or oxidizing reagents is discussed in this Minireview, including methods targeting polar, aromatic, or aliphatic amino acids and peptide termini. [ABSTRACT FROM AUTHOR]

Several novel binaphthyl‐based chiral hypervalent iodine(III) reagents have been prepared and structurally analysed. Various asymmetric oxidative reactions were applied to evaluate the reactivities and stereoselectivities of those reagents. Moderate to excellent yields were observed; however, very low stereoselectivities were obtained. NMR experiments indicated that these reagents are very easily hydrolysed in either chloroform or DMSO solvents leading to the limited stereoselectivities. It is concluded that the use of chiral ligands is an unsuccessful way to prepare efficient stereoselective iodine(III) reagents. [ABSTRACT FROM AUTHOR]

Indole represents one of the most common and important heterocyclic scaffolds omnipresent in a plenty of natural products and medicinal agents. Development of the synthetic routes to 3‐substituted indoles attracts a considerable attention due to a huge amount of biologically relevant molecules containing 3‐substituted indole moiety. Reactions of indoles halogenation, nitration, acylation, and alkylation at the 3d position have been known for several decades and continue developing now. Processes of indoles sulfenylation are much less studied. However, 3‐sulfenylated derivatives possess promising biological properties. This review summarizes nearly 100 references from the middle of the 20th century to 2021, concerning reactions of indoles sulfenylation mediated by iodine and its compounds. The manuscript is divided into the sections according to the classes of compounds used as sulfenylating agents. [ABSTRACT FROM AUTHOR]

The bond strength and nature of a set of 32 Togni‐like reagents have been investigated at the M062X/def2‐TZVP(D) level of theory in acetonitrile described with the SMD continuum solvent model, to rationalize the main factors responsible for their thermodynamic stability in different conformations, and trifluoromethylation capabilities. For the assessment of bond strength, we utilized local stretching force constants and associated bond strength orders, complemented with local features of the electron density to access the nature of the bonds. Bond dissociation energies varied from 31.6 to 79.9 kcal/mol depending on the polarizing power of the ligand trans to CF3. Based on the analysis of the Laplacian of the density, we propose that the charge‐shift bond character plays an important role in the stability of the molecules studied, especially for those containing I−O bonds. New insights on the trans influence and on possible ways to fine‐tune the stability of these reagents are provided. [ABSTRACT FROM AUTHOR]

An original metal‐free method for the convenient preparation of 5‐methyl‐1,2,3,4‐tetrahydropyridine derivatives from simple unactivated alkenes was firstly developed with excellent yields under mild conditions, based on hypervalent iodine compounds in combination with boron fluoride reagents. Mechanism studies have shown that fluorine participates in the reaction as a traceless guiding group, ensuring the successful construction of the Csp2−N bond of tetrahydropyridine derivatives via the selective intramolecular coupling reaction of unactivated alkenes. [ABSTRACT FROM AUTHOR]

Phenyltelluroxane clusters of the composition [{(PhTe)19O24}2I18(solv)] (1) are formed during the hydrolysis of [PhTeI3]2 or the oxidation of various phenyltellurium(II) compounds with iodine under hydrolytic conditions. The compounds consist of two half‐spheres with a {(PhTe)19O24}9+ network, which are connected by 18 iodine atoms. The spherical clusters can accommodate solvent molecules such as pyridine or methanol in the center of two rings formed by iodine atoms. The presence of other metal ions during the cluster formation results in a selective replacement of the central {PhTe}3+ units of each half‐sphere as has been demonstrated with the isolation of [{(PhTe)18({Ca(H2O)2}O24}2I16] (2) and [{(PhTe)18({Y(NO3)(H2O)}O24}2I16] (3). A crownether‐like coordination by six oxygen atoms of the telluroxane network is found for the {Ca(H2O}2}2+ and {Y(NO3)(H2O)}2+ building blocks. Mass spectrometric studies show that considerable amounts of the intact clusters are transferred to the gas phase without dissociation. [ABSTRACT FROM AUTHOR]

Background: The treatment of recurrent mediastinal lymph node metastasis (MLNMs) is challenging. We conducted this study to evaluate the effectiveness and safety of computed tomography (CT)‐guided percutaneous iodine‐125 brachytherapy for MLNMs. Methods: We retrospectively analyzed 33 patients with recurrent MLNMs treated with CT‐guided interstitial implantation of iodine‐125 seeds. Regular contrast‐enhanced CT was conducted to evaluate the tumor response. Follow‐up survival, quality of life, and adverse events were analyzed. Results: The number of implanted seeds was 16–85 (median, 40). The matched peripheral dose was 110–160 Gy. The patients were followed up for 5–24 months (median, 14 months). At the last follow‐up or death, complete response to therapy was achieved in 11 patients (33.3%) and partial response in 18 patients (54.5%). The median survival time of this cohort was 15.2 months (95% confidence interval [CI], 9.9–20.5 months); the estimated one‐ and two‐year survival rates were 68.6% and 31.1%, respectively. The Karnofsky performance score increased significantly after the procedure (p = 0.007). Pneumothorax with pulmonary compression of 30% to 40% occurred in five (15.2%) patients and was cured after drainage. No severe complications occurred. Conclusions: CT‐guided iodine‐125 brachytherapy provided a safe and effective choice for recurrent mediastinal lymph node metastasis with significant local therapeutic effects and minor complications, especially for patients who were not eligible for surgical resection and had failed to benefit from systemic therapy. [ABSTRACT FROM AUTHOR]

Aims: Critical colonization in pressure ulcers delays healing and has been studied. However, local wound management includes no clear strategy for preventing the development of biofilms. Therefore, this multicenter, prospective, observational study was conducted to examine the effect of local management on the biofilm area of pressure ulcers with critical colonization. Methods: Participants were 34 patients with a pressure ulcer deeper than the dermis and in a state of critical colonization. The primary outcome was the change over a week in the proportion of the biofilm area in relation to that of the pressure ulcer area. We investigated the relationship between primary outcome and local wound management. The wound‐blotting method was used for determining the biofilm area. To calculate the change in the biofilm area, baseline proportion was subtracted from proportion 1 week later. Results: Six types of topical treatment were used in three facilities. The proportion of the biofilm area at 1 week follow‐up was significantly smaller with iodine ointment than that without iodine ointment (p =.02). The standardized partial regression coefficient of iodine ointment adjusted by the type of medical facility was −0.26 (p =.003). Conclusion: This study revealed that the use of iodine ointment reduced the proportion of the biofilm area in the pressure ulcer surface. To manage pressure ulcers in a state of critical colonization, these results suggest that local management include the use of iodine ointment. [ABSTRACT FROM AUTHOR]

This review summarizes the progress in the fluorination and fluoroalkylation of electron‐rich systems with diverse fluorine (F) and fluoroalkyl (Rfn) reagents employing hypervalent iodine compounds as initiators in the last few decades. Because of the strong electrophilicity, high oxidizing properties, low toxicity, air and moisture stability, ready availability, ease of handling, and mild reaction conditions, the hypervalent iodine reagents have been widely utilized in modern organic chemistry. In particular, the use of hypervalent iodine reagents to initiate the C−F and C−Rfn (Rfn=CF2H, CF3, perfluoroalkyl, OCH2CF3, SCF3, SeCF3 and etc) bond formation has been increasingly developed. In these reactions, hypervalent iodine compounds behave as powerful oxidants or electrophiles and activate the fluorination/fluoroalkylation reagents, the transition‐metal catalysts, or the substrates to in situ form electrophilic or radical intermediates, which subsequently participate in fluorination, difluoromethylation, trifluoromethylation, perfluoroalkylation, trifluoroethoxylation, fluoroalkylthiolation, trifluoromethylselenolation and others under mild conditions. Although great achievements have been made in this area, they are just the initial phase and still require a wide scope for improvement. It is anticipated that this review will draw much attention from the organic chemistry community and inspire more contributions in the development of new hypervalent‐iodine‐mediated fluorination and fluoroalkylation reactions. [ABSTRACT FROM AUTHOR]

Treatment of a meso‐diarylporphyrin with PhI(OAc)2 in the presence of BF3 ⋅ OEt2 and propionic acid affords the corresponding porphyrinquinone in a high yield (91%). A novel quinone derived from meso‐meso β–β doubly‐fused diporphyrin was obtained as the sole byproduct (16% yield), which exhibits strong panchromatic absorption between 300 and 1000 nm. It has a low HOMO‐LUMO gap owing to expanded and low‐symmetry π‐planes. [ABSTRACT FROM AUTHOR]

SUMMARY Hydrogen can be oxidized by recombination with atmospheric oxygen over a catalyst, such as Pt/Al2O3, at a temperature much lower than that required for thermal oxidation generating heat and water vapor. However, there is potential for the passive autocatalytic recombiner to generate volatile forms of iodine, namely molecular iodine, by catalytic dissociation of various iodine compounds too. The dissociated atomic iodine on the surfaces of the Pt/Al2O3 catalyst is mainly measured at ambient temperature as I 3d peaks in X‐ray photoelectron spectroscopy. It seems that dissociation of iodine compounds on the catalyst surfaces and then production of gaseous I2 by recombination of the dissociated iodine occur prior to the oxidation or reduction of iodine compounds under air or H2. Atomic iodine is predominant on the surfaces of the catalyst in H2 and air conditions, and it is stable even with exposure to H2O. Adsorbed iodine prevents the adsorption of H2 or O2 for recombination to H2O, but it can be desorbed completely at a high temperature. [ABSTRACT FROM AUTHOR]

Site‐selective "cut and sew" transformations employing diazo compounds and hypervalent iodine(III) compounds involve the departure of leaving groups, a "cut" process, followed by a reorganization of the fragments by bond formation, a "sew" process. Bearing controllable cleavage sites, diazo compounds and hypervalent iodine(III) compounds play a critical role as versatile reagents in a wide range of organic transformations because their excellent nucleofugality allows for a large number of unusual reactions to occur. In recent years, the combination of diazo compounds and hypervalent iodine(III) reagents has emerged as a promising tool for developing new and valuable approaches, and has met considerable success. In this Minireview, this combination is systematically illustrated with recent advances in the field, with the aim of elaborating the synthetic utility and potential of this concept as a powerful strategy in organic synthesis. [ABSTRACT FROM AUTHOR]

Site‐selective “cut and sew” transformations employing diazo compounds and hypervalent iodine(III) compounds involve the departure of leaving groups, a “cut” process, followed by a reorganization of the fragments by bond formation, a “sew” process. Bearing controllable cleavage sites, diazo compounds and hypervalent iodine(III) compounds play a critical role as versatile reagents in a wide range of organic transformations because their excellent nucleofugality allows for a large number of unusual reactions to occur. In recent years, the combination of diazo compounds and hypervalent iodine(III) reagents has emerged as a promising tool for developing new and valuable approaches, and has met considerable success. In this Minireview, this combination is systematically illustrated with recent advances in the field, with the aim of elaborating the synthetic utility and potential of this concept as a powerful strategy in organic synthesis. [ABSTRACT FROM AUTHOR]

Introduction. Purkinje system and false tendons (FTs) are related to ventricular arrhythmia, but the association between Purkinje fibers and FTs is not clear. This study investigated the associations of anatomical and electrophysiological characteristics between Purkinje fibers and FTs. Methods and Results. We optimized the protocol of Lugol's iodine solution staining of Purkinje fibers to study the anatomical structure and originated a novel electrophysiological mapping method, named the direct visual mapping (DVM) method, to study the electrophysiological characteristics. By using the above-mentioned innovations in 12 dogs, we found the following. (1) There was no Purkinje fiber found 0.5 cm–1.0 cm below the valve annulus or on the leaflets or chordae tendineae of the mitral valve or adjacent to the top 1/3 of the papillary muscle. (2) Purkinje fibers existed in all FTs, including smaller and tiny FTs. (3) The Purkinje fibers contained in the FTs extended from the proximal to the distal end, and their electrophysiological characteristics were similar to the fibers on the endocardium, including anterograde, retrograde, and decremental conduction and automaticity. Conclusions. Purkinje fibers are commonly found in FTs. The electrophysiological characteristics of the Purkinje fibers contained in FTs are similar to the fibers on the endocardium. FTs might have an anatomical and electrophysiological basis for ventricular arrhythmia. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) at the SMD/M06‐2X/def2‐TZVP//SMD/M06‐2X/SDD,6‐31G(d) level was performed to interrogate the mechanistic details of two oxidative fluorination reactions mediated by hypervalent iodosoarenes (ArIO) in the presence of Lewis acid BF3: (i) formation of a 3‐fluoropyrrolidine from a homoallylic amine and (ii) formation of a fluorinated oxazoline from a benzamide. We found that in both cases, ArIO needs two Lewis acids to be sufficiently activated to mediate the oxidative reactions. When two Lewis acids bind to ArIO, its LUMO mainly centred on the iodine(III) atom becomes energetically more available, resulting in it interacting more strongly with the C–C π orbital of the organic substrate and thus the rate‐determining step of the reaction (an intramolecular nucleophilic attack) being accelerated. Finally, one of these Lewis acids serves as the catalyst and the other one supplies a fluorine atom to the organic substrate. A clear understanding of how ArIO reagents are activated in oxidation of organic substrates could be helpful in designing new oxidative reactions mediated by such hypervalent iodine compounds. [ABSTRACT FROM AUTHOR]

A widely applicable triazole‐substituted chiral aryl iodide is described as catalyst for enantioselective oxidation reactions. The introduction of a substituent in ortho‐position to the iodide is key for its high reactivity and selectivity. Besides a robust and modular synthesis, the main advantage of this catalyst is the excellent performance in a plethora of mechanistically diverse enantioselective transformations, such as spirocyclizations, phenol dearomatizations, α‐oxygenations, and oxidative rearrangements. DFT‐calculations of in situ generated [hydroxy(tosyloxy)iodo]arene isomers give an initial rational for the observed reactivity. [ABSTRACT FROM AUTHOR]

We describe a simple three‐step synthesis of naphtho[2,1‐b:7,8‐b′]bis[1]benzothiophene, which is scalable to multi‐hundred‐gram. We report the subsequent functionalization of this compound into iodine, boronic ester and silane derivatives, which are useful intermediates for various applications. The core structure was analyzed by NMR and single‐crystal X‐ray diffraction, and the physical properties were investigated by cyclic voltammetry, UV/Vis‐ and fluorescence spectroscopy. [ABSTRACT FROM AUTHOR]

Hypervalent iodine(III) compounds with tetrazole ligands C6H5I(N4CR)2 (R CH3, C6H5, 4-CH3C6H4) reacted, in the presence of elemental iodine, with the double bonds in cis-1,- 4-polyisoprene (polyIP) to afford iodo-tetrazolylated polymers. The alkyl-iodide groups in the products of the polyIP functionalization were utilized as macro chain-transfer agents for the iodine-transfer polymerization of methyl methacrylate, which yielded brush polymers with well-defined poly(methyl methacrylate) side chains. In addition, the iodo-tetrazolylated polymers were reacted with NaN3 in DMF at room temperature, and it was noticed that, in addition to nucleophilic substitution, elimination reactions took place. However, the presence of azide groups was taken advantage of and successful click chemistrytype of grafting-onto reactions were carried out with alkynecapped poly(ethylene oxide) in the presence of CuBr and N,N, N0,N00,N00-pentamethyldiethylenetriamine. The thermal decomposition of both the iodo-tetrazolylated and the azidotetrazolylated polymers was exothermic, especially for the latter materials. [ABSTRACT FROM AUTHOR]

In contrast to aryliodine(III) compounds, which have matured into a particularly attractive class of oxidants in modern synthesis, the synthetic potential of related alkyliodine(III) derivatives has remained widely underestimated. This is surprising since several unique synthetic possibilities arise directly from the low stability of their central carbon–iodine bond. In this respect, these high‐oxidation‐state iodine compounds resemble environmentally benign variants of the prominent metal counterparts such as those derived from palladium, nickel and copper. This Concept article summarizes the general reactivity trends in alkyliodine(III) chemistry and discusses selected examples of their strategic use as highly reactive, transient species in organic synthesis and homogeneous catalysis. [ABSTRACT FROM AUTHOR]

Hypervalent iodine compounds are known for their extensive use as potential oxidants in organic synthesis. In spite of the similar reactivity with transition metals, hypervalent iodine reagents are more preferred because of their environmental sustainability. Among several types of hypervalent iodine reagents, trivalent organoiodine(III) reagents are highly popular due to their easy accessibility, stability and controlled oxidizing reactivity. Also, iodine(III) reagents are commercially available and inexpensive. Amines and amides react with iodine(III) oxidants in some specific way to provide a divalent electrophilic ionic species known as a nitrenium ion. Depending on the nature and stability of the nitrenium ion, numerous oxidative transformations to generate valuable functional molecules have been reported. This review encompasses discussions about hypervalent organo iodine(III)‐enabled organic transformations with the involvement of a nitrenium ion as an intermediate. [ABSTRACT FROM AUTHOR]

A catalyst‐ and additive‐free simple and straightforward method for regioselective direct sp2 C–H acetoxylation reaction of aldehyde hydrazones has been achieved at ambient temperature employing PIDA as an acetoxy source. The scope of the reaction has been successfully verified with a wide range of biologically important aldehyde hydrazones with diverse functional group tolerance. The method is highly selective, mild and efficient, operationally simple, rapid and high‐yielding. [ABSTRACT FROM AUTHOR]

Hypervalent iodine compounds constitute a popular class of reagents in organic chemistry. Regardless of whether they are generated in situ from an iodoarene precursor with a terminal oxidant or used in stoichiometric amounts, the resulting separation and waste issues are major challenges en route to sustainable and scalable processes. The electrochemical generation of iodine(III) compounds represents an attractive alternative, since electric current is used as traceless oxidant and unstable or hazardous species are conveniently generated in situ. In this context, we have explored the possibility for the use of iodoarene sulfonates and iodobenzoates as ex‐cell mediators for electrosynthesis in 1,1,1,3,3,3‐hexafluoroisopropanol. While 2‐, 3‐ and 4‐iodobenzoate salts proved to be impractical for various reasons, 2‐ and 4‐iodobenzenesulfonates salts can be selectively oxidized to the iodine(III) species and used for synthetic applications. The ionic tag on the mediator allows for electrolysis without supporting electrolyte additives and enables a straightforward recovery from the product mixture. [ABSTRACT FROM AUTHOR]

A facile method for the regioselective hydrodifluoromethylation of alkenes is reported using difluoroacetic acid and phenyliodine(III) diacetate in tetrahydrofuran under visible‐light activation. This metal‐free approach stands out as it uses inexpensive reagents, does not require a photocatalyst, and displays broad functional group tolerance. The procedure is also operationally simple and scalable, and provides access in one step to high‐value building blocks for application in medicinal chemistry. [ABSTRACT FROM AUTHOR]

We report herein the synthesis of highly substituted and stereochemically well‐defined vinylbenziodoxole (VBX) derivatives through hydrochlorination and iodochlorination of ethynylbenziodoxoles. The hydrochlorination is achieved using pyridine hydrochloride as an HCl source in an anti‐fashion under mild, open‐air conditions to afford a 2‐chlorinated VBX product, which serves as a useful building block for the stereoselective synthesis of trisubstituted alkenes. Meanwhile, iodochlorination with iodine monochloride proceeds in an unusual syn‐pathway, stereoselectively affording a tetrasubstituted VBX derivative. [ABSTRACT FROM AUTHOR]

Egg disinfection is an important practice that prevents potential disease transfer, but currently allowable disinfection regimes do not completely eliminate external egg membrane microbes. In this experiment, newly fertilized and water‐hardened landlocked fall Chinook Salmon Oncorhynchus tshawytscha eggs were submersed for 10 min in povidone‐iodine solutions containing 0, 100, 200, and 400 mg/L active iodine. External egg bacterial numbers (CFUs) were quantified after each disinfection treatment, and egg survival (%) was calculated at the eyed stage. All of the disinfection treatments significantly reduced CFUs compared with untreated controls. However, eggs from the 400‐mg/L iodine treatment had significantly lower CFUs (2.20 ± 0.59 [mean ± SE]) than the 100‐mg/L (10.43 ± 8.01) and 200‐mg/L (8.10 ± 1.51) treatments. Percent survival was not significantly different among any of the treatments; survival was 18.86 ± 5.17%, 19.17 ± 4.76%, and 20.16 ± 5.27% in the eggs subjected to 100 mg/L, 200 mg/L, and 400 mg/L iodine, respectively. These results indicate that 10‐min treatments of 400 mg/L active iodine on landlocked fall Chinook Salmon eggs provide the most microbial reduction with no effect on subsequent egg survival. [ABSTRACT FROM AUTHOR]

ABSTRACT: The arylthio‐substituted tetrathiafulvalenes (Ar‐S‐TTFs) are electron donors having three reversible states, neutral, cation radical, and dication. The charge‐transfer (CT) between Ar‐S‐TTFs (TTF1—TTF3) and iodine (I2) is reported herein. TTF1—TTF3 show the CT with I2 in the CH2Cl2 solution, but they are not completely converted into cation radical state. In CT complexes of TTF1—TTF3 with I2, the charged states of Ar‐S‐TTFs are distinct from those in solution. TTF1 is at cation radical state, and TTF2—TTF3 are oxidized to dication. The iodine components in complexes show various structures including 1‐D chain of V‐shaped (I5)–, and 2‐D and 3‐D iodine networks composed of I2 and (I3)–. [ABSTRACT FROM AUTHOR]

Abstract: Non‐iodinated arenes can be easily and selectively converted into (diacetoxyiodo)arenes in a single step under mild conditions by using iodine triacetates as reagents. The oxidative step is decoupled from the synthesis of hypervalent iodine(III) reagents, which can now be prepared conveniently in a one‐pot synthesis for subsequent reactions without prior purification. The chemistry of iodine triacetates was also expanded to heteroatom ligand exchanges to form novel inorganic hypervalent iodine compounds. [ABSTRACT FROM AUTHOR]

Abstract: Metal‐free dehydrogenative couplings of aryliodanes with phenols to afford 2‐hydroxy‐2′‐iodobiaryls have been developed. This reaction proceeds through ligand exchange on the hypervalent iodine atom followed by a [3,3] sigmatropic rearrangement and with complete regioselectivity. This coupling, in combination with in situ oxidation by mCPBA, enables the convenient conversion of iodoarenes into desirable biaryls. The obtained biaryls have convertible iodo and hydroxy groups in close proximity, and are thus synthetically useful, as exemplified by the controlled syntheses of π‐extended furans and a substituted [5]helicene. DFT calculations clearly revealed that the rearrangement is sigmatropic, with C−C bond formation and I−O bond cleavage proceeding in a concerted manner. Acetic acid, which was found to be the best solvent for this protocol, renders the iodine atom more cationic and thus accelerates the sigmatropic rearrangement. [ABSTRACT FROM AUTHOR]

Abstract: The tin–tin bond cleavage of hexaorganodistannanes by nucleophiles is a long‐known reaction and widely used for stannate formation or stannyl group transfer. Herein, we detail our experiments to provide analytical evidence for the existence of the reasonably stable anionic complexes [XSn(C2F5)3{Sn(C2F5)3}]− (X=Cl, Br, I, Sn(C2F5)3) derived from hexakis(pentafluoroethyl)distannane. NMR investigations at low temperature lend further mechanistic insights. Thus, by detection of the imposing ion [Sn(C2F5)3{Sn(C2F5)3}2]−, one can surmise that the chemistry of Sn2(C2F5)6 has more in common with the isolobal iodine than with classical distannanes. [ABSTRACT FROM AUTHOR]

Abstract: The tin–tin bond cleavage of hexaorganodistannanes by nucleophiles is a long‐known reaction and widely used for stannate formation or stannyl group transfer. Herein, we detail our experiments to provide analytical evidence for the existence of the reasonably stable anionic complexes [XSn(C2F5)3{Sn(C2F5)3}]− (X=Cl, Br, I, Sn(C2F5)3) derived from hexakis(pentafluoroethyl)distannane. NMR investigations at low temperature lend further mechanistic insights. Thus, by detection of the imposing ion [Sn(C2F5)3{Sn(C2F5)3}2]−, one can surmise that the chemistry of Sn2(C2F5)6 has more in common with the isolobal iodine than with classical distannanes. [ABSTRACT FROM AUTHOR]