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Nuclear fuel reprocessing plant releases several kinds of radioactive nuclides, mainly 3H and 129I, into the oceans. Radio iodine causes thyroid dose. Iodine accumulates in several marine species such as wakame and abalone, which are food materials. Therefore, an analysis of iodine behavior in the marine environment is important to assess the impact of 129I. Iodine in seawater exists mainly in two chemical forms: iodide (I-) and iodate (IO3-). Their environmental behaviors are different. Thus, understanding these behaviors is important to assess the environmental behavior of total iodine. In this study, iodate and iodide transfer between seawater and abalone (Haliotis discus hannai) with 125I tracer was observed., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The monitoring of radioactive iodide levels is of great significance in environmental science and cancer radiotherapy. In this work, a high-throughput, radiation-resistant, and visualized electrochemiluminescence (ECL) strategy was developed for detection of iodide ions. Herein, the hydrophobic ruthenium derivative (Ru(bpy) 3 [B(C 6 F 5 ) 4 ] 2 ) (bpy = bipyridyl) was doped in tertiary amine-coupled polymer dots (N-PFO Pdots) to synthesize self-enhanced Pdots (Ru@Pdots), which showed extremely high ECL intensity in absence of coreactant. Due to the efficient ECL resonance energy transfer between Ru(bpy) 3 [B(C 6 F 5 ) 4 ] 2 and N-PFO, the Ru@Pdots exhibited 18 times higher ECL intensity compared with bare N-PFO Pdots. Besides, Ru@Pdots also showed 220-times higher ECL intensity compared with Ru(bpy) 3 [B(C 6 F 5 ) 4 ] 2 doped coreactant-dependent Pdots (Ru@PFO Pdots). Using Ru@Pdots as ECL emitters, an ECL imaging array was designed for iodide ion detection, which exhibited a detection range of 0.8 nM-4 μM and a limit of detection of 0.1 nM. In this strategy, iodide ions were oxidized as iodide free radicals on the surface of the electrode, which could further consume the nitrogen radical of Ru@Pdots and effectively quench the ECL signal. This method also showed good specificity, radiation-resistant performance, and accuracy in actual seawater sample testing, which indicated its value in marine environmental monitoring, nuclear security, and cancer radiotherapy.

Although the xylose mutarotation and transformation have been investigated largely separately, their relationship has been rarely systematically elaborated. The effect of several factors such as xylose concentration, temperature, and salt concentration, affecting the mutarotation of xylose are discussed. Nine alkali halides (LiCl, NaCl, KCl, LiBr, NaBr, KBr, LiI, NaI, and KI) are used to test salt effects. The relationship between xylose rotation rate constant (k M ), specific optical rotation at equilibrium ([α] eqm ), α/β ratio, H chemical shift difference (ΔΔδ), Gibbs free energy difference (ΔG), hydrogen ion or hydroxide ion concentration ([H + ] or [OH - ]), and xylose conversion is discussed. Different salts dissolved in water result in different pH of the solutions, which affect the mutarotation of xylose, with the nature of both cation and anion. Shortly, the smaller the cation radius is and the larger the anion radius is, the greater the mutarotation rate is. In the dehydration of xylose to furfural in salty solutions, xylose conversion is positively correlated to mutarotation rate, H + or OH - concentration, and the energy difference between α-xylopyranose and β-xylopyranose. Although the [α] eqm of xylose is positively correlated with α/β configuration ratio, there is no obvious correlation with xylose dehydration. The conversion to furfural in chlorides is superior to that in bromines and iodides, which is due to the fact that the pH of chloride salts is smaller than that of the corresponding bromide and iodized salts. Higher H + concentration prefers to accelerate the formation of furfural. In basic salt solutions, the xylulose selectivity is higher than that of furfural at the initial stage of reaction. The furfural selectivity and carbon balance are better in acidic condition rather than in basic condition. In H 2 O-MTHF (2-Methyltetrahydrofuran) biphasic system, the optimal furfural selectivity of 81.0 % is achieved at 190 °C in 1 h with the assistance of LiI and a little HCl (0.2 mmol, 8 mmol/L in aqueous phase). A high mutarotation rate represents rapid xylose conversion, but a high furfural selectivity prefers in acidic solutions, which would be perfect if organic solvents were available to form biphasic systems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Peracetic acid (PAA) is an alternative disinfectant for saline wastewaters, and hypohalous acids are typically regarded as the reactive species for oxidation and disinfection. However, new results herein strongly suggest that reactive radicals instead of HOI primarily contributed to decontamination during PAA treatment of iodine-containing wastewater. The presence of I - could greatly accelerate the micropollutants (e.g., sulfamethoxazole (SMX)) transformation by PAA. Chemical probes experiments and electron paramagnetic resonance analysis demonstrate acetylperoxyl radical rather than reactive iodine species primarily responsible for SMX degradation. The kinetic model was developed to further distinguish and quantify the contribution of radicals and iodine species, as well as to elucidate the transformation pathways of iodine species. Density functional theory calculations indicated that the nucleophilic attack of I - on the peroxide bond of PAA could form unstable O-I bond, with the transition state energy barrier for radical generation lower than that for HOI formation. The transformation of iodine species was regulated by acetylperoxyl radical to generate nontoxic IO 3 - , greatly alleviating the iodinated DBPs formation in saline wastewaters. This work provides mechanistic insights in radical-regulated iodine species transformation during PAA oxidation, paving the way for the development of viable and eco-friendly technology for iodide containing water treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Achieving a desired whitening effect through short treatments without using peroxide and without compromising the integrity of tooth enamel remains a challenge in teeth whitening. Here, we developed a highly safe and efficient photodynamic therapy (PDT) strategy based on visible light-activated bismuth oxyiodide nanoparticles for nondestructive tooth whitening. The Bi 7 O 9 I 3 nanoparticles (NPs) exhibited efficient photocatalytic activity owing to their narrow band gap, effectively harnessing the broad spectrum of visible light to generate ample electrons and holes. Meanwhile, the presence of oxygen vacancies, low oxidation state Bi 3+ and the high specific surface area endow Bi 7 O 9 I 3 NPs with effective electron-hole separation ability and potent redox potentials. Empowered by these characteristics, Bi 7 O 9 I 3 NPs effectively catalyzed O 2 into radicals (O 2 •- ), facilitating the degradation of dental surface pigment molecules for tooth whitening. Concurrently, they eradicated oral bacteria and bacterial biofilms adhering to tooth surfaces, thereby having a positive effect on the effectiveness of tooth whitening. This PDT strategy with Bi 7 O 9 I 3 NPs shows broad application prospects in tooth whitening., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Herein, a label-free single-molecule electrical sensor was first proposed for the ultrasensitive and selective detection of iodide ions in human urine. Single-molecule conductance measurements in different halogen ion solutions via scanning tunneling microscopy break junction (STM-BJ) clearly revealed that I - ions strongly affect the stability and displacement distance (Δ z ) distribution of molecular junctions. Theoretical calculations prove that the specific adsorption of I - ions modifies the surface properties and weakens the molecular adsorption. Furthermore, the average conductance peak area versus the logarithm of the I - ion concentration has a very good linear relationship in the range of 5 × 10 -6 to 5 × 10 -10 M, with a correlation coefficient of 0.99. This quantitative analysis remains valid in the presence of interfering ions of SO 4 2- , ClO 4 - , Br - , and Cl - as well as interfering molecules of ascorbic acid, uric acid, dopamine, and cysteine. A cross-comparison of the human urine detection results of this single-molecule electrical sensor with those of the clinical method of As 3+ -Ce 4+ catalytic spectrophotometry revealed an average difference of 0.9%, which decreased the detection time of 2 h with the traditional method to approximately 15 min. This work proves the promising practical potential of the single-molecule electrical technique for relevant clinical analysis.

The lateral flow assay (LFA) is an ideal technology for at-home medical diagnostic tests due to its ease of use, cost-effectiveness, and rapid results. Despite these advantages, only few LFAs, such as the pregnancy and COVID-19 tests, have been translated from the laboratory to the homes of patients. To date, the medical applicability of LFAs is limited by the fact that they only provide yes/no answers unless combined with optical readers that are too expensive for at-home applications. Furthermore, LFAs are unable to compete with the state-of-the-art technologies in centralized laboratories in terms of detection limits. To address those shortcomings, we have developed an electrochemical readout procedure to enable quantitative and sensitive LFAs. This technique is based on a voltage-triggered in-situ dissolution of gold nanoparticles, the conventional label used to visualize target-specific signals on the test line in LFAs. Following the dissolution, the amount of gold is measured by electroplating onto an electrode and subsequent electrochemical quantification of the deposited gold. The measured current has a low noise, which achieves superior detection limits compared to optical techniques where background light scattering is limiting the readout performance. In addition, the hardware for the readout was developed to demonstrate translatability towards low-cost electronics., Competing Interests: Declaration of competing interest The authors declare the following financial interests or personal relationships which may be considered as potential competing interests: Yves Blickenstorfer, Vlastimil Jirasko, Alexander Tanno, Josephine Löhle and Yulya Mamedava were affiliated with Hemetron AG during their contribution to the manuscript. The other authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Contamination of water sources is a major environmental problem with far-reaching consequences for humanity. Organic substances are among the most widespread and persistent pollutants. Advanced oxidation processes, especially photocatalysis, have been considered as one of the most promising technologies for organic pollution control. In this study, hybrid photocatalysts based on N-doped TiO 2 , which exhibits activity in the visible region of the spectrum, and different content of octahedral Mo 6 bromide and iodide cluster complexes were synthesized to achieve the highest efficiency of the formed S-scheme photocatalytic system under white light irradiation. According to the data obtained, the resulting materials are nanoparticles with a diameter of ∼10 nm exhibiting absorption up to ∼550 nm. Photocatalytic studies were performed using model organic molecules - the more colored rhodamine B (RhB) and the less colored antibiotic tetracycline (TET). The most active samples showed high efficiencies against both pollutants with k eff ∼0.3-0.4 and 0.4-0.5 min -1 , respectively, while the activity of iodide complexes was ∼1.3 times higher than that of bromide complexes. The stability of the catalysts is preserved for up to 5 cycles of TET photodegradation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Global sea to air iodine emissions, along with organic emissions and their oxidation products, have increased tremendously. This work presents a comprehensive analysis of the humidity mediated changes in ageing aerosols comprising iodide and water soluble dicarboxylic acid using aerosol micro-Raman spectroscopy. The studies in the model system, sodium iodide-malonic acid mixed aerosols, unveiled the depletion in iodide. Mechanistic insights gleaned through comparative studies conducted under inert (nitrogen) and oxidative (air) atmospheres reveal the iodide depletion occurs possibly via oxidation to molecular iodine. The reaction involves gaseous components, diffusion of which across the particles will be impacted by the physical state of the particles, such as viscosity, which in turn is intricately linked to ambient humidity levels. To this end, studies on the temporal evolution of the reaction at three distinct RHs covering 30-80% revealed the enhanced progression of the reaction with increasing humidity. Given that geographical locations serving as major sources for atmospheric iodine typically experience high humidity, these reactions could emerge as an additional process controlling iodine speciation in ageing aerosols., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Freeze-induced acceleration of I - oxidation and the consequent iodination of dissolved organic matter (DOM) contribute to the formation of organoiodine compounds (OICs) in cold regions. The formed OICs may be a potentially important source of risk and are very closely with the environment and human health. Herein, we investigated the acceleration effects of the freeze process on I - oxidation and the formation of OICs. In comparison to reactive iodine species (RIS) formed in aqueous solutions, I - oxidation and RIS formation were greatly enhanced in frozen solution and were affected by pH, and the content of I - and O 2 . Freeze-thaw process further promoted I - oxidation and the concentration of RIS reached 45.7 µmol/L after 6 freeze-thaw cycles. The consequent products of DOM iodination were greatly promoted in terms of both concentration and number. The total content of OICs ranged from 0.02 to 2.83 µmol/L under various conditions. About 183-1197 OICs were detected by Fourier transform ion cyclotron resonance mass spectrometry, and more than 96.2% contained one or two iodine atoms. Most OICs had aromatic structures and were formed via substitution and addition reactions. Our findings reveal an important formation pathway for OICs and shed light on the biogeochemical cycling of iodine in the natural aquatic environment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

This work describes a novel method for converting bismuth triiodide (BiI 3 ) microplates into bismuth oxyiodide (BiOI) nanoflakes under ultrasonic irradiation. To produce BiOI nanoflakes with a high yield and high purity, the conversion process was carefully adjusted. Rapid reaction kinetics and increased mass transfer are benefits of the ultrasonic-assisted approach that result in well-defined converted BiOI nanostructures with superior characteristics. The produced BiOI nanoflakes were examined utilizing a range of analytical methods, such as Transmission Electron Microscopy (TEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The progress in the ultrasonic conversion process with time was monitored through diffuse reflectance spectroscopy (DRS). The outcomes demonstrated the effective conversion of BiI 3 microplates into crystalline, homogeneous, high-surface-area BiOI nanoflakes. Additionally, the degradation of organic dyes (methylene blue) under ultraviolet (UV) light irradiation was used to assess the photocatalytic efficacy of the produced BiOI nanoflakes. Because of their distinct morphology and electrical structure, the BiOI nanoflakes remarkably demonstrated remarkable photocatalytic activity, outperforming traditional photocatalysts. The ability of BiOI nanoflakes to effectively separate and utilize visible light photons makes them a viable option for environmental remediation applications. This work not only shows the promise of BiOI nanoflakes for sustainable photocatalytic applications but also demonstrates a simple and scalable approach to their manufacturing. The knowledge gathered from this work opens up new avenues for investigating ultrasonic-assisted techniques for creating sophisticated nanomaterials with customized characteristics for a range of technological uses.

Both copper (Cu 2+/+ ) and iodine (I - ) are essential elements in all living organisms. Increasing the intracellular concentrations of Cu or I ions may efficiently inhibit tumor growth. However, efficient delivery of Cu and I ions into tumor cells is still a challenge, as Cu chelation and iodide salts are highly water-soluble and can release in untargeted tissue. Here we report mitochondria-targeted Cu-I cluster nanoparticles using the reaction of Cu + and I - to form stable bovine serum albumin (BSA) radiation-induced phosphors (Cu-I@BSA). These solve the stability issues of Cu + and I - ions. Cu-I@BSA exhibit bright radioluminescence, and easily conjugate with the emission-matched photosensitizer and targeting molecule using functional groups on the surface of BSA. Investigations in vitro and in vivo demonstrate that radioluminescence under low-dose X-ray irradiation excites the conjugated photosensitizer to generate singlet oxygen, and combines with the radiosensitization mechanism of the heavy atom of iodine, resulting in efficient tumor inhibition in female mice. Furthermore, our study reveals that BSA protection causes the biodegradable Cu-I clusters to release free Cu and I ions and induce cell death by modulating mitochondrial function, damaging DNA, disrupting the tricarboxylic acid cycle, decreasing ATP generation, amplifying oxidative stress, and boosting the Bcl-2 pathway., (© 2024. The Author(s).)

Extensive investigations are being conducted on gold nanoparticles focusing on their applications in biosensors, laser phototherapy, targeted drug delivery and bioimaging utilizing advanced detection techniques. In this work, an electrochemical sensor was developed based on graphite carbon nitride supported gold nanoparticles. Carbon nitride supported gold nanoparticles (Au-CN) was synthesized by applying a deposition-precipitation route followed by a chemical reduction technique. The composite system was characterized by X-ray diffraction and X-ray photo electron spectroscopy methods. Electron microscopy analysis confirmed the formation of gold nanoparticles within the size range of 5-15 nm on the carbon nitride support. Carbon nitride supported gold based sensor was employed for the electrochemical detection of iodide ion and l-cysteine. The limit of detection and sensitivity of the sensor was attained 8.9 μM and 0.96 μAμM⁻ 1 cm⁻ 2 , respectively, for iodide ion, while 0.48 μM and 5.8 μAμM⁻ 1 cm⁻ 2 , respectively, was achieved for the recognition of cysteine. Furthermore, a paper-based electrochemical device was developed using the Au-CN hybrid system that exhibited promising results in detecting iodide ions, highlighting its potential for economic and portable device applications., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Peptide-bound histidines and imidazoles are important constituents of dissolved organic matter in water, and understanding the formation of halogenated disinfection byproduct (DBP) formation from these compounds during disinfection is important for ensuring a safe drinking water supply. Previous studies suggested that histidine has low reactivity with chlorine only; this study indicates that iodide substantially enhances histidine reactivity with the disinfectant at a time scale from days to hours. Mono- and di-iodinated histidines were identified as dominant transformation products with cumulative molar yields of 3.3 % at 6 h and they were stable in water over 7 days. These products were formed via electrophilic substitution of iodine to imidazole ring when hypoiodous acid reacted with histidine sidechain. Bromide minimally influenced the formation yields of these iodinated products, and higher pH increased yields up to 12 % for pH in the range 5-9. The cumulative concentration of low-molecular-weight DBPs, such as trihalomethanes and haloacetic acids, was less than 0.3 % under the same conditions. Similar iodinated imidazole analogs were also identified from other imidazoles (i.e., imidazole-carboxylic and phenyl-imidazole-carboxylic acids). This study demonstrated that peptide-bound histidine and imidazoles can serve as important precursors to iodinated aromatic DBPs, facilitating the identification of less-known iodinated DBPs., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

At inflammatory sites, immune cells generate oxidants including H₂O₂. Myeloperoxidase (MPO), released by activated leukocytes employs H₂O₂ and halide/pseudohalides to form hypohalous acids that mediate pathogen killing. Hypochlorous acid (HOCl) is a major species formed. Excessive or misplaced HOCl formation damages host tissues with this linked to multiple inflammatory diseases. Previously (Redox Biology, 2020, 28, 101331) we reported that iodide (I⁻) modulates MPO-mediated protein damage by decreasing HOCl generation with concomitant hypoiodous acid (HOI) formation. HOI may however impact on protein structure, so in this study we examined whether and how HOI, from peroxidase/H₂O₂/I⁻ systems ± Cl⁻, modifies proteins. Experiments employed MPO and lactoperoxidase (LPO) and multiple proteins (serum albumins, anastellin), with both chemical (intact protein and peptide mass mapping, LC-MS) and structural (SDS-PAGE) changes assessed. LC-MS analyses revealed dose-dependent iodination of anastellin and albumins by LPO/H 2 O 2 with increasing I⁻. Incubation of BSA with MPO/H 2 O 2 /Cl⁻ revealed modest chlorination (Tyr286, Tyr475, ∼4 %) and Met modification. Lower levels of these species, and extensive iodination at specific Tyr and His residues (>20 % modification with ≥10 μM I⁻) were detected with increasing I⁻. Anastellin dimerization was inhibited by increasing I⁻, but less marked changes were observed with albumins. These data confirm that I⁻ competes with Cl⁻ for MPO and is an efficient HOCl scavenger. These processes decrease protein chlorination and oxidation, but result in extensive iodination. This is consistent with published data on the presence of iodinated Tyr on neutrophil proteins. The biological implications of protein iodination relative to chlorination require further clarification., Competing Interests: Declaration of competing interest MJD declares consultancy contracts with Novo Nordisk A/S, and is a Director and major shareholder in the start-up company Seleno Therapeutics plc. These funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. Prof. Michael Davies is also an Editorial Board Member for Free Radical Biology and Medicine but was not involved in the editorial review or the decision to publish this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

We present a novel approach for iodide sensing based on the heavy-atom effect to quench the green fluorescent emission of organosilicon nanoparticles (OSiNPs). The fluorescence of OSiNPs was significantly quenched (up to 97.4% quenching efficiency) in the presence of iodide ions (I - ) through oxidation by hydrogen peroxide. Therefore, OSiNPs can serve as a fluorescent probe to detect I - with high selectivity and sensitivity. The highly selective response is attributed to the hydrophilic surface enabling good dispersion in aqueous solutions and the lipophilic core allowing the generated liposoluble I 2 to approach and quench the fluorescence of OSiNPs. The linear working range for I - was from 0 to 50 μM, with a detection limit of 0.1 μM. We successfully applied this nanosensor to determine iodine content in edible salt. Furthermore, the fluorescent OSiNPs can be utilized for the determination of total antioxidant capacity (TAC). Antioxidants reduce I 2 to I - , and the extent of quenching by the remaining I 2 on the OSiNPs indicates the TAC level. The responses to ascorbic acid, pyrogallic acid, and glutathione were investigated, and the detection limit for ascorbic acid was as low as 0.03 μM. It was applied to the determination of TAC in ascorbic acid tablets and fruit juices, indicating the potential application of the OSiNP-based I 2 sensing technique in the field of food analysis., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

The development of green and efficient deuteration methods is of great significance for various fields such as organic synthesis, analytical chemistry, and medicinal chemistry. Herein, we have developed a dehalogenative deuteration strategy using piezoelectric materials as catalysts in a solid-phase system under ball-milling conditions. This non-spontaneous reaction is induced by mechanical force. D 2 O can serve as both a deuterium source and an electron donor in the transformation, eliminating the need for additional stoichiometric exogenous reductants. A series of (hetero)aryl iodides can be transformed into deuterated products with high deuterium incorporation. This method not only effectively overcomes existing synthetic challenges but can also be used for deuterium labelling of drug molecules and derivatives. Bioactivity experiments with deuterated drug molecule suggest that the D-ipriflavone enhances the inhibitory effects on osteoclast differentiation of BMDMs in vitro., (© 2024 Wiley-VCH GmbH.)

It has recently been discovered that HFPO-TA (a processing aid in the production of fluoropolymers) has high levels of bioaccumulation and biotoxicity. Hydrated electrons (e aq - ) have been proposed to be potent nucleophiles that may decompose PFAS. Unlike previous studies in which the generation of e aq - was often restricted to anaerobic or highly alkaline environments, in this study, we applied the UV/SO 3 2- /I - process under mild conditions of neutrality, low source chemical demand, and open-air, which achieved effective degradation (81.92 %, 0.834 h -1 ) and defluorination (48.99 %, 0.312 h -1 ) of HFPO-TA. With I - as the primary source of e aq - , SO 3 2- acting as an I - regenerator and oxidizing substances scavenger, UV/SO 3 2- /I - outperformed others under mild circumstances. The e aq - were identified as the main active species by quenching experiments and electron paramagnetic resonance (EPR). During degradation, the first site attacked by e aq - was the ether bond (C6-O7), followed by the generation of HFPO-DA, TFA, acetic and formic acid. Degradation studies of other HFPOs have shown that the defluorination of HFPOs was accompanied by a clear chain-length correlation. At last, toxicological experiments confirmed the safety of the process. This study updated our understanding of the degradation of newly PFASs and the application of e aq - mediated photoreductive approaches under mild conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

There is an urgent need for nonopioid treatments for chronic and neuropathic pain to provide effective alternatives amid the escalating opioid crisis. This study introduces novel compounds targeting the α9 nicotinic acetylcholine receptor (nAChR) subunit, which is crucial for pain regulation, inflammation, and inner ear functions. Specifically, it identifies novel substituted carbamoyl/amido/heteroaryl dialkylpiperazinium iodides as potent agonists selective for human α9 and α9α10 over α7 nAChRs, particularly compounds 3f , 3h , and 3j . Compound 3h (GAT2711) demonstrated a 230 nM potency as a full agonist at α9 nAChRs, being 340-fold selective over α7. Compound 3c was 10-fold selective for α9α10 over α9 nAChR. Compounds 2 , 3f , and 3h inhibited ATP-induced interleukin-1β release in THP-1 cells. The analgesic activity of 3h was fully retained in α7 knockout mice, suggesting that analgesic effects were potentially mediated through α9* nAChRs. Our findings provide a blueprint for developing α9*-specific therapeutics for pain.

Iodate is a stable form of iodine species in the natural environment. This work found that the abiotic photosensitized reduction of iodate by fulvic acid (FA) is highly enhanced in frozen solution compared to that in aqueous solution. The freezing-induced removal of iodate by FA at an initial pH of 3.0 in 24 h was lower than 10% in the dark but enhanced under UV (77.7%) or visible light (31.6%) irradiation. This process was accompanied by the production of iodide, reactive iodine (RI), and organoiodine compounds (OICs). The photoreduction of iodate in ice increased with lowering pH (pH 3-7 range) or increasing FA concentration (1-10 mg/L range). It was also observed that coexisting iodide or chloride ions enhanced the photoreduction of iodate in ice. Fourier transform ion cyclotron resonance mass spectrometric analysis showed that 129 and 403 species of OICs (mainly highly unsaturated and phenolic compounds) were newly produced in frozen UV/iodate/FA and UV/iodate/FA/Cl - solution, respectively. In the frozen UV/iodate/FA/Cl - solution, approximately 97% of generated organochlorine compounds (98 species) were identified as typical chlorinated disinfection byproducts. These results call for further studies of the fate of iodate, especially in the presence of chloride, which may be overlooked in frozen environments.

Formic and acetic acids are the most abundant gaseous organic acids and play the key role in the atmospheric chemistry. In iodine-adduct chemical ionization mass spectrometry (CIMS), the low utilization efficiency of methyl iodide and humidity interference are two major issues of the vacuum ultraviolet (VUV) lamp initiated CIMS for on-line gaseous formic and acetic acids analysis. In this work, we present a new CIMS based on VUV lamp, and the ion-molecular reactor is separated into photoionization and chemical ionization zones by a reducer electrode. Acetone was added to the photoionization zone, and the VUV photoionization acetone provided low-energy electrons for methyl iodide to generate I - , and the addition of acetone reduced the amount of methyl iodide by 2/3. In the chemical ionization zone, a headspace vial containing ultrapure water was added for humidity calibration, and the vial changes the sensitivity as a function of humidity from ambiguity to well linear correlation (R 2 > 0.95). With humidity calibration, the CIMS can quantitatively measure formic and acetic acids in the humidity range of 0%-88% RH. In this mode, limits of detection of 10 and 50 pptv are obtained for formic and acetic acids, respectively. And the relative standard deviation (RSD) of quantitation stability for 6 days were less than 10.5%. This CIMS was successfully used to determine the formic and acetic acids in the underground parking and ambient environment of the Shandong University campus (Qingdao, China). In addition, we developed a simple model based formic acid concentration to assess vehicular emissions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

We present experimental evidence that atomic and molecular iodine, I and I 2 , are produced spontaneously in the dark at the air-water interface of iodide-containing droplets without any added catalysts, oxidants, or irradiation. Specifically, we observe I 3 - formation within droplets, and I 2 emission into the gas phase from NaI-containing droplets over a range of droplet sizes. The formation of both products is enhanced in the presence of electron scavengers, either in the gas phase or in solution, and it clearly follows a Langmuir-Hinshelwood mechanism, suggesting an interfacial process. These observations are consistent with iodide oxidation at the interface, possibly initiated by the strong intrinsic electric field present there, followed by well-known solution-phase reactions of the iodine atom. This interfacial chemistry could be important in many contexts, including atmospheric aerosols.

Metal oxides play a critical role in the abiotic transformation of iodine species in natural environments. In this study, we investigated iodide oxidation by manganese dioxides (β-MnO 2 , γ-MnO 2 , and δ-MnO 2 ) in frozen and aqueous solutions. The heterogeneous reaction produced reactive iodine (RI) in the frozen phase, and the subsequent thawing of the frozen sample induced the gradual transformation of in situ-formed RI to iodate or iodide, depending on the types of manganese dioxides. The freezing-enhanced production of RI was observed over the pH range of 5.0-9.0, but it decreased with increasing pH. Fulvic acid (FA) can be iodinated by I - /MnO 2 in aqueous and frozen solutions. About 0.8-8.4% of iodide was transformed to organoiodine compounds (OICs) at pH 6.0-7.8 in aqueous solution, while higher yields (10.4-17.8%) of OICs were obtained in frozen solution. Most OICs generated in the frozen phase contained one iodine atom and were lignin-like compounds according to Fourier transform ion cyclotron resonance/mass spectrometry analysis. This study uncovers a previously unrecognized production pathway of OICs under neutral conditions in frozen environments.

Iodized table salt provides iodide that is essential for health. However, during cooking, we found that chloramine residuals in tap water can react with iodide in table salt and organic matter in pasta to form iodinated disinfection byproducts (I-DBPs). While naturally occurring iodide in source waters is known to react with chloramine and dissolved organic carbon (e.g., humic acid) during the treatment of drinking water, this is the first study to investigate I-DBP formation from cooking real food with iodized table salt and chloraminated tap water. Matrix effects from the pasta posed an analytical challenge, necessitating the development of a new method for sensitive and reproducible measurements. The optimized method utilized sample cleanup with Captiva EMR-Lipid sorbent, extraction with ethyl acetate, standard addition calibration, and analysis using gas chromatography (GC)-mass spectrometry (MS)/MS. Using this method, seven I-DBPs, including six iodo-trihalomethanes (I-THMs) and iodoacetonitrile, were detected when iodized table salt was used to cook pasta, while no I-DBPs were formed with Kosher or Himalayan salts. Total I-THM levels of 11.1 ng/g in pasta combined with cooking water were measured, with triiodomethane and chlorodiiodomethane dominant, at 6.7 and 1.3 ng/g, respectively. Calculated cytotoxicity and genotoxicity of I-THMs for the pasta with cooking water were 126- and 18-fold, respectively, compared to the corresponding chloraminated tap water. However, when the cooked pasta was separated (strained) from the pasta water, chlorodiiodomethane was the dominant I-THM, and lower levels of total I-THMs (retaining 30% of the I-THMs) and calculated toxicity were observed. This study highlights an overlooked source of exposure to toxic I-DBPs. At the same time, the formation of I-DBPs can be avoided by boiling the pasta without a lid and adding iodized salt after cooking.

The heterogeneous reaction of ozone and iodide is both an important source of atmospheric iodine and dry deposition pathway of ozone in marine environments. While the iodine generated from this reaction is primarily in the form of HOI and I 2 , there is also evidence of volatile organoiodide compound emissions in the presence of organics without biological activity occuring [M. Martino, G. P. Mills, J. Woeltjen and P. S. Liss, A new source of volatile organoiodine compounds in surface seawater, Geophys. Res. Lett. , 2009, 36 , L01609, L. Tinel, T. J. Adams, L. D. J. Hollis, A. J. M. Bridger, R. J. Chance, M. W. Ward, S. M. Ball and L. J. Carpenter, Influence of the Sea Surface Microlayer on Oceanic Iodine Emissions, Environ. Sci. Technol. , 2020, 54 , 13228-13237]. In this study, we evaluate our fundamental understanding of the ozonolysis of iodide which leads to gas-phase iodine emissions. To do this, we compare experimental measurements of ozone-driven gas-phase I 2 formation in a flow tube to predictions made with the kinetic multilayer model for surface and bulk chemistry (KM-SUB). The KM-SUB model uses literature rate coefficients used in current atmospheric chemistry models to predict I 2(g) formation in pH-buffered solutions of marine composition containing chloride, bromide, and iodide compared to solutions containing only iodide. Experimentally, I 2(g) formation was found to be suppressed in solutions containing seawater levels of chloride compared to solutions containing only iodide, but the model does not predict this effect using literature rate constants. However, the model is able to predict this trend upon adjustment of two specific reaction rate constants. To more closely represent true oceanic conditions, we add an organic component to the proxy seawater solutions using material generated from Thalassiosira pseudonana phytoplankton cultures. Whereas the rate of ozone deposition is unaffected, the formation rate of I 2(g) is strongly suppressed in the presence of biological organic material, indicative of a sink or reduction of reactive iodine formed during the oxidation process.

Objective . Polycrystalline mercuric iodide photoconductive converters fabricated using particle-in-binder techniques (PIB HgI 2 ) provide significantly more detected charge per x-ray interaction than from a-Se and CsI:Tl converters commonly used with active matrix flat-panel imagers (AMFPIs). This enhanced sensitivity makes PIB HgI 2 an interesting candidate for applications involving low x-ray exposures-since the relatively high levels of additive electronic noise exhibited by AMFPIs incorporating a-Se and CsI:Tl reduce detective quantum efficiency (DQE) performance under such conditions. A theoretical study is reported on an approach for addressing a major challenge impeding practical use of PIB HgI 2 converters-the high lag exhibited by the material (over 10%) which would lead to undesirable image artifacts in applications involving acquisition of consecutive images such as digital breast tomosynthesis. Approach . Charge transport modeling accounting for the trapping and release of holes (thought to be the primary contributor to lag) was used to examine signal properties, including lag, of pillar-supported Frisch grids embedded in the photoconductor for 100 μ m pitch AMFPI pixels. Performance was examined as a function of electrode voltage, grid pitch (center-to-center distance between neighboring grid wires) and the ratio of grid wire width to grid pitch. Main results . Optimum grid designs maximizing suppression of signal generated by hole transport, without significantly affecting the total signal due to electron and hole transport, were identified and MTF was determined. For the most favorable designs, additional modeling was used to determine DQE. The results indicate that, through judicious choice of grid design and operational conditions, first frame lag can be significantly reduced to below 1%-less than the low levels exhibited by a-Se. DQE performance is shown to be largely maintained as exposure decreases-which should help to maintain good image quality. Significance . Substantial reduction of lag in PIB HgI 2 converters via incorporation of Frisch grids has been demonstrated through modeling., (© 2023 Institute of Physics and Engineering in Medicine.)

Iodine is widely used as an antimicrobial reagent for water disinfection in the wilderness and outer space, but residual iodine and iodide need to be removed for health reasons. Currently, it is challenging to remove low concentrations of iodine and iodide in water (≈5 ppm). Furthermore, the remediation of iodine and iodide across a broad temperature range (up to 90 °C) has not previously been investigated. In this work, we report a nitrate dimer-directed synthesis of a single-crystalline ionic hydrogen-bonded crosslinked organic framework (H C OF-7). H C OF-7 removes iodine and iodide species in water efficiently through halogen bonding and anion exchange, reducing the total iodine concentration to 0.22 ppm at room temperature. Packed H C OF-7 columns were employed for iodine/iodide breakthrough experiments between 23 and 90 °C, and large breakthrough volumes were recorded (≥18.3 L g -1 ). The high iodine/iodide removal benchmarks recorded under practical conditions make H C OF-7 a promising adsorbent for water treatment., (© 2022 Wiley-VCH GmbH.)

Samarium diiodide is a versatile single electron transfer (SET) agent with various applications in organic chemistry. Lewis structures regularly insinuate the existence of a ketyl radical when samarium diiodide binds a carbonyl group. The study presented here investigates this electron transfer by the means of computational chemistry. All electron CASPT2 calculations with the inclusion of scalar relativistic effects predict an endotherm electron transfer from samarium diiodide to acetone. Energies calculated with the PBE0-D3(BJ) functional and a small core pseudopotential are in good agreement with CASPT2. The calculations confirm the experimentally measured increase of the samarium diiodide reduction potential through the addition of hexamethylphosphoramide also known as HMPA.

Ferrate(VI) (Fe(VI)) is utilized as an efficient and environmentally friendly water treatment agent that can be widely used for degradation of (in)organic pollutants in practical applications. However, only a few spectrophotometric methods for Fe(VI) determination were reported. In this study, a novel method for determining trace levels of aqueous Fe(VI) was developed based on the fact that Fe(VI) reacts with iodide at acidic pH to form iodine, which subsequently is treated with starch to yield the blue starch-iodine complex measured spectrophotometrically at 590 nm. The key measurement parameters, including acidic medium, starch dosages, temperature, time, and addition order were optimized to improve the sensitivity of detection. The increase in absorbance at 590 nm was linear with respect to Fe(VI) added (0.022-50 µM). Its sensitivity was determined as (4.61 ± 0.05) × 10 4  M -1  cm -1 , which was higher than that of existing spectrophotometric methods. The principle for Fe(VI) determination was studied by investigating stoichiometry, kinetics, and mechanism of Fe(VI) reaction with iodide. The molar stoichiometry of Fe(VI) with I 3 - species was determined to be 1:2. The reaction of Fe(VI) with iodide followed a second-order rate law with first order in each reactant and displayed apparent anti-Arrhenius kinetics, then its reaction pathway was proposed as well. Furthermore, the established method was successfully applied to measure Fe(VI) in various environmental water samples. The results show that the proposed approach is simple, convenient, highly reproducible and extremely sensitive, and is also expected to be of use for kinetic studies of Fe(VI) reaction with (in)organic compounds under acidic conditions., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The copper-catalyzed enantioselective intermolecular radical 1,2-carboamination of alkenes with readily accessible alkyl halides is an appealing strategy for producing chiral amine scaffolds. The challenge arises from the easily occurring atom transfer radical addition between alkyl halides and alkenes and the issue of enantiocontrol. We herein describe a radical alkene 1,2-carboamination with sulfoximines in a highly chemo- and enantioselective manner. The key to the success of this process is the conceptual design of a counterion/highly sterically demanded ligand coeffect to promote the ligand exchange of copper(I) with sulfoximines and forge chiral C-N bonds between alkyl radicals and the chiral copper(II) complex. The reaction covers alkenes bearing distinct electronic properties, such as aryl-, heteroaryl-, carbonyl-, and aminocarbonyl-substituted ones, and various radical precursors, including alkyl chlorides, bromides, iodides, and the CF 3 source. Facile transformations deliver many chiral amine building blocks of interest in organic synthesis and related areas.

In this paper, in the presence of trimethylsilyl iodide, the direct ortho -C-H hydroxyalkylation/methylation of aryl iodines was effectively realized via palladium/norbornene cooperative catalysis when low-cost tetrahydrofuran and 1,2-dimethoxyethane were used as alkyl sources. Heck, Suzuki, and Sonogashira coupling and hydrogenation were all compatible with the reaction as termination steps. In addition, neuromuscular agents and cardiovascular agents were synthesized in one step by this method, showing their potential application value.

A complete protocol is presented for the speciation analysis of 129 I for both inorganic and organic iodine in seawater using coprecipitation and solid-phase extraction (SPE) combined with accelerator mass spectrometry (AMS). By modifying the iodide separation process and adding a crossover removal step, the improved coprecipitation method significantly reduces the cross-contamination of iodide and iodate to less than 0.05% in the speciation analysis of inorganic 129 I, with the separation efficiencies of about 95% and 93% for iodide and iodate, respectively. The SPE-DOI method for the dissolved organic 129 I (DO 129 I) analysis was developed, whereby we report the first direct observation of DO 129 I/DO 127 I atom ratios in seawater in this paper. 129 I species in seawater from Tokyo Bay were analysed. The 129 I results demonstrated that our protocol for speciation analysis of 129 I is reliable and provided new insights into understanding the iodine cycle.

Aromatic halides constitute a valuable class of building blocks that are commonly used in organic synthesis. In this study, we demonstrate usage of aryl bromides and aryl iodides in C-Br or C-I bond formation. Methyl 2-bromobenzoate and 2-nitrophenyl iodides were developed as mild and effective bromination and iodination reagents for functionalization of arene-tethered diols. This efficient cascaded catalysis can be applied to the total syntheses of natural product Mafaicheenamine A and Claulamine A.

Visible light active 1D/2D-NiMoO 4 /BiOI nanocomposite photocatalyst has been constructed by single step solvothermal method. Various compositions of NiMoO 4 /BiOI nanocomposites are prepared by loading different amounts of nickel molybdate (NiMoO 4 ) (1, 2, 3 wt%) to the bismuth oxy iodide (BiOI) and investigated by XRD, FTIR, SEM, EDAX, TEM, UV-vis DRS, and PL analysis. Among the as-prepared photocatalysts, 1 wt% NiMoO 4 incorporated BiOI (NMBI-1) showed superior photocatalytic activity with a rate constant of 0.0442 min -1 for methylene blue degradation. While the bandgap values of pure BiOI and NiMoO 4 are 1.94 and 2.43 eV, respectively, the optimized NMBI-1 exhibited a lower bandgap energy of 1.64 eV, and showed about 2 and 3.7 times higher photodegradation ability than the pure NiMoO 4 and BiOI, respectively, towards MB removal under visible light. The NMBI-1 nanocomposite photocatalyst is stable even after four cycles, indicating an excellent photostability and recyclability. Charge carriers on the interface of NiMoO 4 and BiOI easily transferred via the newly formed heterojunction, thereby increasing the photocatalytic performance. Photochemically formed h + and . OH are found to be the major species in the MB removal under visible light illumination. Therefore, the 1D/2D-NiMoO 4 /BiOI nanocomposite photocatalyst materials may be considered for the wastewater remediation processes., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Long-term exposure to excessive iodine via drinking water significantly increases the risk of thyroid diseases. Further, the mechanisms and feasible technologies for iodine removal are far from being well elucidated. In this study, we constructed a heterogeneous Bi 2 O 3 @MnO 2 interface with oxidation and adsorption efficiency toward iodide (I - ), and investigated the performance and mechanisms involved in iodine removal. Bi 2 O 3 @MnO 2 at the optimized Bi/Mn ratio of 0.05:1 had a maximum adsorption capacity of 1.19, 1.21, and 1.06 mg/g toward I - , iodine elemental (I 2 ), and iodate (IO 3 - ), respectively. According to the density functional theory (DFT) calculation, Bi 2 O 3 @MnO 2 had an adsorption energy of -2.34, -2.11, and -3.89 eV for I - , I 2 , and IO 3 - , and exhibited a better band structure and state density character for iodine removal. Based on the results of XPS, HPLC, and LC-ICP-MS characterization, Bi 2 O 3 plays an important role in adsorbing and capturing I - whereas MnO 2 dominates the moderate oxidation of I - and the adsorption of I - and I 2 . The adsorbed I - and I 2 concentrations on the Bi 2 O 3 @MnO 2 surfaces were 146.3 μg/L and 18.3 μg/L. Notably, IO 3 - was not detected owing to its moderate oxidation effect. The coexisting ions of chloride (Cl - ) and bromide (Br - ) tended to occupy the Bi 2 O 3 lattice and form insoluble BiOCl and BiOBr. Further, reductive species, such as sulphite (SO 3 2- ), may reduce MnO 2 to Mn(III) and Mn(II). The synergistic effect between moderate oxidation and adsorption led to Bi 2 O 3 @MnO 2 with high iodine removal capability. Overall, this study proposes a strategy for designing suitable interfaces and adsorbents for iodine removal; however, further studies are necessary to advance its application in practice., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

The 1,3-oxazolidine-2-thiones (OZTs) are important chiral molecules, especially in asymmetric synthesis. These compounds serve as important active units in biologically active compounds. Herein, carbohydrate anchored OZTs were explored to develop a copper-catalyzed C-S bond formation with aryl iodides. Chemoselective S -arylation was observed, with copper iodide and dimethylethylenediamine (DMEDA) as the best ligand in dioxane at 60-90 °C. The corresponding chiral oxazolines were obtained in reasonable to good yields under relatively mild reaction conditions. This approach is cheap, as using one of the cheapest transition metals, a simple protocol and various functional group tolerance make it a valuable strategy for getting S -substituted furanose-fused OZT. The structures of the novel carbohydrates were confirmed by NMR spectroscopy and an HRMS analysis., Competing Interests: The authors declare no conflict of interest.

A Pd-catalyzed, native α-amino acid derivative-directed benzylic C-H bond arylation/oxidation with aryl iodides was developed. The natural amino acid auxiliary could serve as a desired building block for formation of 5-aryl-1,4-benzodiazepin-2-ones after removal of the trifluoroacetyl protecting group. The bifunctional reaction probably proceeded through a sequential benzylic arylation/oxidation process.

Strategies for synthesizing polyhydroxylated piperidines such as iminosugars have received broad attention. These substances are known to interact with carbohydrate related enzymes, glycosidases and glycosyltransferases, to which also the large enzyme families of chitin synthases and cellulose synthases belong. Many chemical and biological aspects of chitin synthases remain unexplored due to the fact that modulating substances are hardly available or expensive. Starting from enantiopure D- and L-amino acids, a series of iminosugars was prepared by a Lewis acid-catalyzed cyclization of amino acid-derived unsaturated aldehydes as key step. Therefore, different Lewis acids were tested. For samarium diiodide we observed a superior stereoselectivity in comparison to iron(III) chloride and methylaluminium dichloride. To increase water solubility for testing and measurement of enzyme activity, the cyclization products were further functionalized. We established a novel biological chitin synthesis test system which allows quantitative investigation of chitin synthesis in the chitin fiber producing diatom algae Thalassiosira in vivo under the light microscope. None of the compounds displayed cytotoxicity, but two of the four iminosugars increased the length of the chitin fibers produced. This is a strong indicator that these compounds mimic carbohydrates responsible for restarting chitin polymerization.

Here, we present a visible light-catalyzed hydroalkylation of aryl-alkenes affording C-C bonds using aryl-alkenes and alkyl iodides. We demonstrate the formation of various hydroalkylation products in excellent yields, with primary, secondary, and tertiary alkyl iodides being tolerated in the reaction. Mechanistic experiments reveal a pathway consisting of halogen atom transfer followed by a radical-polar crossover mechanism delivering the desired hydroalkylation products.

The well-defined Pd(I) metalloradical [Pd(P t Bu 3 ) 2 ] + reacts with aryl and alkyl iodides at room temperature, yielding [Pd(P t Bu 3 )(μ-I)] 2 and phosphonium salts. Pd(II) aryl/alkyl derivates, reflecting net radical oxidative addition of the substrate to the metalloradical, are generated during the reaction and two examples have been isolated and crystallographically characterised.

Herein, we developed an efficient and transition-metal-free multicomponent coupling reaction for the synthesis of aroyloxyl alkyl iodides. In the reaction among 2,4,6-triarylboroxines, THF, TMSCF 3 , LiOH, and NaI, five-component reactions could be precisely controlled by modulating CF 3 SO 2 Na, supplying one type of aroyloxyl alkyl iodides in moderate to high yields. The reaction exhibits good functional group tolerance and a wide substrate scope and can be easily transformed into other useful compounds. The mechanism is proposed on the basis of the control experiments.

Asymmetric cross-electrophile difunctionalization of tethered alkenes has become a powerful tool for the production of chiral cyclic scaffolds; however, the current studies all focus on carbocyclization reactions. Herein, we report an N -cyclization-alkylation reaction and thus showcase the potential of heterocyclization for accessing new enantioenriched cyclic architectures. This work establishes a new approach for enantioselective aza-Heck cyclization/cross-coupling sequence, which remains a long-standing unsolved challenge for the synthetic community. The reaction proceeds with primary, secondary, and a few tertiary alkyl iodides, and the use of newly defined ligands gave highly enantioenriched pyrrolines with improved molecular diversity under mild conditions. The presence of imine functionality allows for further structural variations.

Reductive cyclizations of carbonyl compounds, mediated by samarium(II) diiodide (SmI 2 , Kagan's reagent), represent an invaluable platform to generate molecular complexity in a stereocontrolled manner. In addition to classical ketone and aldehyde substrates, recent advances in radical chemistry allow the cyclization of lactone and lactam-type substrates using SmI 2 . In contrast, acyclic esters are considered to be unreactive to SmI 2 and their participation in reductive cyclizations is unprecedented. Here, we report a diastereoselective radical 1,4-ester migration process, mediated by SmI 2 , that delivers stereodefined alkene hydrocarboxylation products via radical cyclization of acyclic ester groups in α-carbomethoxy δ-lactones. Isotopic labeling experiments and computational studies have been used to probe the mechanism of the migration. We propose that a switch in conformation redirects single electron transfer from SmI 2 to the acyclic ester group, rather than the "more reactive" lactone carbonyl. Our study paves the way for the use of elusive ketyl radicals, derived from acyclic esters, in SmI 2 -mediated reductive cyclizations.

The selective difluoromethylene insertion into a C-Cu bond is a challenging task and is currently limited to either a single CF 2 insertion into CuCF 3 or double CF 2 insertions into CuC 6 F 5 (or ( Z )-CF 3 CF = CFCu). Achieving both selective single and double CF 2 insertions into the same C-Cu bond is even more difficult. Herein, highly controllable single and double CF 2 insertions into CuCF 2 H species with a TMSCF 2 Br reagent have been described, affording two previously unknown fluoroalkylcopper species "Cu(CF 2 ) n CF 2 H" ( n = 1 and 2) independently under different reaction conditions. This work represents the first example of both single and double CF 2 insertions into the same C-Cu bond in a highly selective manner. The synthetic value of the obtained "Cu(CF 2 ) n CF 2 H" ( n = 1 and 2) species is demonstrated by their reactions with aryl iodides, halogenation agents, and cinnamyl chloride, which enables the direct transfer of HCF 2 CF 2 and HCF 2 CF 2 CF 2 moieties into organic molecules. The key to controllable fluorocarbon chain elongation from C 1 to C 2 and from C 1 to C 3 is presumably attributed to the different reactivities of "Cu(CF 2 ) n CF 2 H" species ( n = 0, 1, 2 and 3) and the loading of the TMSCF 2 Br reagent.

Long-term exposure to excessive iodine via drinking water presents health risks. Moderate oxidation of iodide (I - ) to iodine (I 2 ) has a better iodine removal effect than excessive oxidation to iodate (IO 3 - ). This study combines computational and experimental methods to construct a heterogeneous interface with synchronous I - moderate oxidation and I 2 adsorption to increase the total iodine removal. Compared to other forms of crystal manganese dioxide (MnO 2 ), theoretical calculations predict that MnO 2 with a γ-crystal structure has the lowest adsorption energy, that is, -1.20 eV, and a slight overlap between the conduction and valence bands, which favors electron transfer between I - and Mn(IV) and I 2 adsorption. Thus, γ-type MnO 2 was designed by adjusting the precursor Mn sources and hydrothermal reaction conditions. The liquid chromatography-inductively coupled plasma-mass spectrometry and high-performance liquid chromatography confirmed that the total iodine concentration in water decreased from 173.7 to 36.3 μg/L after 2 h, with 200 mg/L γ-MnO 2 dosage lower than the national standard of 0.1 mg/L. A minute proportion of I - in water was converted to IO 3 - (approximately 1.1 μg/L). The current I - adsorbent performed better than previously reported ones. During iodine removal, most of the I - migrated from water to the surface of γ-MnO 2 , and the ratio of I - to I 2 was determined to be 1:0.6 by X-ray photoelectron spectroscopy. This study evaluates iodine species transformation and an optimum strategy for heterogeneous interface design; it is promising for treating high-iodine groundwater.

The dynamics of low energy electron attachment to the thio-substituted uracil analog 2-thiouracil are investigated using time-resolved photoelectron spectroscopy (TRPES) of iodide-2-thiouracil (I - ·2TU) binary clusters. In these experiments, the anions are excited at pump energies of 4.16 and 4.73 eV, and the ensuing dynamics are probed by photodetachment at 1.59 and 3.18 eV. Upon excitation near the vertical detachment energy (4.16 eV), dipole bound (DB) and valence bound (VB) anion signals appear almost instantaneously, and the DB state of the 2TU anion undergoes an ultrafast decay (∼50 fs). At 4.73 eV, there is no evidence for a DB state, but features attributed to two VB states are seen. The transient negative ions formed by photoexcitation decay by autodetachment and I - fragmentation. The I - dissociation rates and their dependence on excitation energy agree reasonably well with the Rice-Ramsperger-Kassel-Marcus calculations. Notable differences with respect to TRPES of the related iodide-uracil anion are observed and discussed.

We report palladium-catalyzed aminocarbonylation of (hetero)aryl iodides with α-amino acid esters as nucleophiles. The synthesized N-capped α-amino acids are biologically important building blocks. The mild conditions provide products with high enantioselectivity at 80 °C in 35 min. The reactions are performed under air in a sealed vessel using chloroform as an in situ CO source. For the first time, regioselective carbonylation of histidine is also presented.

Iodine is a naturally-occurring halogen in natural waters generally present in concentrations between 0.5 and 100 µg L -1 . During oxidative drinking water treatment, iodine-containing disinfection by-products (I-DBPs) can be formed. The formation of I-DBPs was mostly associated to taste and odor issues in the produced tap water but has become a potential health problem more recently due to the generally more toxic character of I-DBPs compared to their chlorinated and brominated analogues. This paper is a systematic and critical review on the reactivity of iodide and on the most common intermediate reactive iodine species HOI. The first step of oxidation of I - to HOI is rapid for most oxidants (apparent second-order rate constant, k app > 10 3  M -1 s -1 at pH 7). The reactivity of hypoiodous acid with inorganic and organic compounds appears to be intermediate between chlorine and bromine. The life times of HOI during oxidative treatment determines the extent of the formation of I-DBPs. Based on this assessment, chloramine, chlorine dioxide and permanganate are of the highest concern when treating iodide-containing waters. The conditions for the formation of iodo-organic compounds are also critically reviewed. From an evaluation of I-DBPs in more than 650 drinking waters, it can be concluded that one third show low levels of I-THMs (<1 µg L -1 ), and 18% exhibit concentrations > 10 µg L -1 . The most frequently detected I-THM is CHCl 2 I followed by CHBrClI. More polar I-DBPs, iodoacetic acid in particular, have been reviewed as well. Finally, the transformation of iodide to iodate, a safe iodine-derived end-product, has been proposed to mitigate the formation of I-DBPs in drinking water processes. For this purpose a pre-oxidation step with either ozone or ferrate(VI) to completely oxidize iodide to iodate is an efficient process. Activated carbon has also been shown to be efficient in reducing I-DBPs during drinking water oxidation., (Copyright © 2022. Published by Elsevier Ltd.)

Halogen bonding to phosphorus atoms remains uncommon, with relatively few examples reported in the literature. Here, the preparation and investigation of the cocrystal bis(dicyclohexylphenylphosphine)(1,6-diiodoperfluorohexane) by X-ray crystallography and solid-state multinuclear magnetic resonance spectroscopy is described. The crystal structure features two crystallographically unique C-I...P halogen bonds [d I...P = 3.090 (5) Å, 3.264 (5) Å] and crystallographic disorder of one of the 1,6-diiodoperfluorohexane molecules. The first of these is the shortest and most linear I...P halogen bond reported to date. 13 C, 19 F, and 31 P magic angle spinning solid-state NMR spectra are reported. A 31 P chemical shift change of -7.0 p.p.m. in the cocrystal relative to pure dicyclohexylphenylphosphine, consistent with halogen bond formation, is noted. This work establishes iodoperfluoroalkanes as viable halogen bond donors when paired with phosphorus acceptors, and also shows that dicyclohexylphenylphosphine can act as a practical halogen bond acceptor.

Herein, we reported the first versatile and expeditious protocol for the diversity-oriented synthesis (DOS) of fluoroalkylated amines via the photoinduced palladium-catalyzed cross coupling of 1,3-dienes, amines and fluoroalkyl iodides, which features excellent 3,4- and 1,4-selectivity controlled by fluoroalkyl iodides, a broad substrate scope as well as good function group tolerance, and could be extended to the late-stage modification of bioactive molecules.