Molecular Iodine Research Articles

Effect of Molecular Iodine on the Electrophoretic Properties of Suspensions for Electrophoretic Deposition

Effect of Molecular Iodine on the Electrophoretic Properties of Suspensions for Electrophoretic Deposition

Precision spectroscopy and frequency determination of the hyperfine components of the P(63) 4-4 transition of molecular iodine near 652 nm

Precision spectroscopy and frequency determination of the hyperfine components of the P(63) 4-4 transition of molecular iodine near 652 nm

Acyclic Diaminocarbene Platinum(IV) Complexes Synthesized by the Oxidative Addition of MeI and I<sub>2</sub>

The oxidative addition of methyl iodide or molecular iodine to the bis(С,N-chelate) deprotonated diaminocarbene platinum(II) complexes [Pt{C(N(H)Ar)(NC(N(H)Ph)N(Ph)}2] (Ar = C6H3-2,6-Me2 (Xyl), C6H2-2,4,6-Me3 (Mes), and C6H4-4-Me (pTol)) affords the corresponding platinum(IV) derivatives in a yield of 89–99%. The addition of CF3CO2H is accompanied by the protonation of the nitrogen atoms of the diaminocarbene fragment to form the cationic complexes [[PtI(X)-{C(N(H)Ar)(NC(N(H)Ph)N(Ph)}2]CF3CO2H (X = Me, I). The structures of the compounds are determined by elemental analysis; high resolution mass spectrometry with electrospray ionization (ESI HRMS); IR spectroscopy; 1H, 13C{1H}, 19F{1H}, and 195Pt{1H} NMR spectroscopy; 2D NMR spectroscopy (1H,1Н COSY, 1H,1Н NOESY, 1H,13C HSQC, 1H,13C HMBC, 1H,15N HSQC, 1H,15N HMBC), and X-ray diffraction (XRD) and thermogravimetric analyses. The synthesized platinum(IV) complexes are thermally stable to 200–260°C and are electroneutral molecules with the octahedral coordination sphere formed by two deprotonated diaminocarbene C,N-chelate substituents and iodine and methyl or two iodine atoms localized in the apical positions.

Preventive and therapeutic effects of molecular iodine in a model of diabetes mellitus induced by streptozotocin

Diabetes mellitus (DM) is a multifactorial condition that involves oxidative alterations and dysbiosis of the gut microbiota associated with an imbalance in glucose metabolism. Therefore, the need to develop integrative therapies that are both effective and have fewer side effects has become evident in recent years. Molecular iodine (I2) has antioxidant effects in preclinical hyperglycemic models. The present work analyzes the preventive and therapeutic effects of oral I2 supplementation in a DM model induced by low doses of streptozotocin (STZ). Male CD1 mice (12 weeks old) were divided into the following groups: control, STZ (20 mg/kg/day, i.p., for 5 days), I2 (0.2 mg/Kg in drinking water), preventive (STZ + I2), and therapeutic (I2 supplementation from day 35 to day 90; STZ + I2(Ther)). The supplementation with I2 prevented and normalized hyperglycemia, hypercholesterolemia, and hypertriglyceridemia associated with STZ, preserving pancreatic, liver, muscle, and adipose tissue morphology and normalizing inflammatory gene induction (TLR2, TLR4, NFkβ, TNFα) in several tissues. Furthermore, compared to the STZ group, the presence of I2 favored a more significant abundance of beneficial bacteria that support the integrity of the intestinal epithelial barrier and higher α-diversity. In conclusion, the I2 supplement has preventive and therapeutic effects, reducing oxidative damage and reestablishing microbiota diversity following STZ exposure.

Accurate calibration spectra for precision radial velocities

Astronomical spectrographs require calibration of their dispersion relation, for which external sources like hollow-cathode lamps or absorption-gas cells are useful. Laser frequency combs (LFCs) are often regarded as ideal calibrators because they provide the highest accuracy and dense sampling, but LFCs are facing operational challenges such as generating blue visual light or tunable offset frequencies. As an example of an external source, we aim to provide a precise and accurate frequency solution for the spectrum of molecular iodine absorption by referencing to an LFC that does not cover the same frequency range. We used a Fourier Transform Spectrometer (FTS) to produce a consistent frequency scale for the combined spectrum from an iodine absorption cell at 5200– 6200 Å and an LFC at 8200 Å. We used 17 807 comb lines to determine the FTS frequency offset and compared the calibrated iodine spectrum to a synthetic spectrum computed from a molecular potential model. In a single scan, the frequency offset was determined from the comb spectrum with an uncertainty of ∼1 cms−1. The distribution of comb line frequencies is consistent with no deviation from linearity. The iodine observation matches the model with an offset of smaller than the model uncertainties of ∼1 m s−1, which confirms that the FTS zero point is valid outside the range covered by the LFC, and that the frequencies of the iodine absorption model are accurate. We also report small systematic effects regarding the iodine model’s energy scale. We conclude that Fourier Transform Spectrometry can transfer LFC accuracy into frequency ranges not originally covered by the comb. This allows us to assign accurate frequency scales to the spectra of customized wavelength calibrators. The calibrators can be optimized for individual spectrograph designs regarding resolution and spectral bandwidth, and requirements on their long-term stability are relaxed because FTS monitoring can be performed during operation. This provides flexibility for the design and operation of calibration sources for high-precision Doppler experiments.

Rapid Iodination Kinetic Studies of o-Toluidine in Aqueous Medium: A Pharmacokinetic Insight from QSAR and Molecular Docking of its Iodo Product with Cytochrome P450

The kinetic data of uncatalyzed rapid iodination of o-toluidine using molecular iodine in aqueous medium was investigated by employing hydrodynamic voltammetry (HV) technique. The frequency factor, activation energy and entropy change accompanying the reaction were evaluated. The reaction followed second order kinetics that had a half-life of 90 s and specific reaction rate 888.87 M s–1 at 22.1 ºC. The iodo product was formed via the green route in the aqueous solvent. The physico-chemical characteristics, lipophilicity, water solubility and pharmacokinetic parameters were derived by QSAR analysis. The docking of the iodo product with cytochrome P450 exhibited steric and physiological complementarity of the ligand-protein interface through hydrogen bonding and pi-pi stacking interactions, indicating that the product exhibited metabolic activity was similar to the existing drugs.

Depletion of iodide in ageing aerosols and the role of humidity: A case study of mixed sodium iodide-malonic acid aerosol

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.

Enabling defect control or polyiodide formation regimes in halide perovskites

Defect engineering in oxide materials is typically achieved through manipulation of oxygen pressure and temperature, followed by quenching which freezes the concentration of point defects. Unlike oxides, halide perovskites equilibrate with gaseous atmosphere at room temperature. Information on defect engineering in halide perovskites that utilize the concentration of gaseous species is scarce and controversial. In this report we address this controversy by studying the interaction of MAPbI3 with molecular iodine over a wide range of partial pressures and reveal the two regimes of such interaction: defect control regime and polyiodide formation regime switching at ∼20 % of the saturated iodine pressure. In defect control regime the material undergoes reversible changes in semiconductor properties, while in polyiodide formation regime the material undergoes irreversible changes in crystallinity and microstructure. These findings emphasize the manifold role of molecular iodine for this class of materials and provides researchers with the experimental framework that can be utilized to tune stoichiometry and conductivity of halide perovskites to further enhance the performance and stability metrics of the corresponding devices.

Measurement of transition frequencies and hyperfine constants of molecular iodine at 520.2 nm

We measured the transition frequencies of the hyperfine components in the four lines (P(34) 39-0, R(36) 39-0, P(33) 39-0, and R(35) 39-0) of the B-X transitions of molecular iodine at 520.2 nm. The 520.2 nm laser was generated by wavelength-converting the output of a 1560.6 nm external-cavity diode laser using a dual-pitch periodically poled lithium niobate (PPLN) waveguide. The frequencies were measured by counting the heterodyne beats between the laser stabilized at the frequencies of the hyperfine components and a frequency comb synchronized with a hydrogen maser. We determined the transition frequencies of the a1 components with relative uncertainties of 1×10−11; the uncertainty was limited by the impurity of the molecular iodine in the cell. From the measured hyperfine splitting frequencies, we calculated the hyperfine constants of these four transitions to obtain the rotational dependence of the excited-state hyperfine constants.

Radical decomposition of hydrogen peroxide catalyzed by iodide for degradation of organic dyes

The decomposition of hydrogen peroxide into hydroxyl radical, a powerful oxidizing agent, has aroused the interest of the scientific community due to the numerous possible applications, mainly in the treatment of effluents. In this work, the potential of using iodide ions as precursors of the hydroxyl radical was evaluated. Iodide, in addition to being theoretically viable, simultaneously leads to the production of molecular iodine, which also has an oxidizing characteristic, and can contribute to the efficiency of the process. The results demonstrated that iodide ions act by promoting the radical decomposition of H2O2 and that the process is dependent on the pH of the reaction medium, with the generation of radical hydroxyl only manifesting itself at pH 2.5 and 3.0. The removal results proved that the anionic or cationic nature of the dye interferes with the reaction mechanism. For methylene blue, a cationic dye, a small portion of TOC was removed by oxidation (7.9 to 20.6%) and the remainder occurred by adsorption (79.4 and 92.1%). The interaction of methylene blue with the surface of molecular iodine prevents its contact with the iodide ions present in the reaction medium, allowing it to remain in a solid state in solution and act as an adsorbent, contributing to better efficiency. For the tartrazine yellow dye, an anionic dye, there was no formation of solid iodine, indicating the absence of an adsorptive process, with the oxidation mechanism, showing removal of 11.3 to 18.9%, similar to the results found for the removal of blue. methylene by oxidation.

Croconic Acid Integrated Zwitterionic Conjugated Porous Polymer for Effective Iodine Adsorption.

Given the rapid growth of the nuclear sector, effective treatment of radioactive iodine is critical. Herein, we report the synthesis and the iodine adsorption properties of croconic acid (CTPB) and squaric acid (STPB) containing π-conjugated novel zwitterionic conjugated porous polymers (CPPs). The CPPs have been synthesized through a condensation reaction of tris(4-aminophenyl)benzene with croconic acid or squaric acid in high yields (~95%). The ionic nature of the polymers promoted high iodine/polyiodide vapour adsorption capacity of up to 4.6 g/g for CTPB and 3.5 g/g for STPB under ambient pressure at 80 °C. The zwitterionic framework (croconic acid or squaric acid units) coupled with the aromatic units is expected to effectively capture molecular iodine (I2) and polyiodides (I3- and I5-). The iodine adsorption properties of the polymers have been studied using Fourier-Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Brauner-Emmett-Teller (BET) analysis, and Raman Spectroscopy. Besides this work, there are only three ionic units for effective iodine adsorption. This work demonstrates the importance of zwitterionic units in the porous network reported for iodine adsorption and separation.

Formation to Transportation: En-Route Fission-Facilitated Formation of Spheres in a Phosphorus-Based Porous Organic Polymer for Transportation of Iodine.

Despite its potential as a clean power source to meet rising electricity demands, nuclear energy generates radioactive waste, including isotopes of iodine, that pose significant environmental and health risks. There is a growing demand to capture radioactive iodine and repurpose it effectively. However, achieving this dual functionality with a single material remains a significant challenge. This study explores phosphorus-based porous organic polymers (P-POPs) as probes for these dual functionalities. By employing 4-formyl(triphenyl)phosphine (BB1) and phenyl-1,4-diacetonitrile (BB2) under the Knoevenagel polycondensation method, P-POPs (PKPOPs) have been synthesized that exhibit a smooth spherical morphology, which efficiently captures and release iodine under ambient conditions, facilitating efficient transportation of molecular iodine. This novel approach aims to potentially transform nuclear waste into valuable organic feedstock via an iodination reaction. The innovative application of PKPOP has also been demonstrated for iodination reactions using ball mills and under continuous flow conditions, showcasing its potential for safer waste management and utilization.

Dual-mode iodine sensing: Colorimetric and electrochemical detection methods using functionalized gold nanoparticles

Iodine in natural and treated waters exists mainly as iodide, iodate, and molecular iodine (I2). I2 is a highly volatile and reactive species impacting biological and chemical systems. Iodine, a vital micronutrient, is essential for human and animal growth and metabolism. It also plays a crucial role in synthesising artificial adrenaline within the metabolic processes of humans and animals. It is also widely used as an antiseptic, disinfectant, and for emergency water disinfection. Moreover, iodine deficiency can result in various diseases, especially hypothyroidism and goitre. Given its critical functions, it is imperative to have a straightforward, dependable, and efficient method for monitoring iodine levels. This study introduces a simple and innovative I2 detection system based on its reactivity, toxicity, and role as an indicator of oxidative conditions in water. It operates in terms of based on optical and electrochemical signal changes, utilising the anti-aggregation mechanism of gold nanoparticles (AuNPs) and 6-mercaptohexanol (MHA) for sensitive and selective detection under mild conditions. I2 determination is achieved by observing the colour change in AuNPs, which is influenced by competitive interactions between MHA, I2, and AuNPs. The optical detection system, with its low detection limit (LOD=260 nM), is based on the straightforward observation of colour changes. On the other hand, the electrochemical detection method utilises changing redox peaks observed in anodic region, providing selective and sensitive I2 detection (LOD=100 nM). The probe effectively detects the presence of I2 in real water samples as a practical application. Moreover, the proposed method revolutionises I2 detection by incorporating a smartphone for signal reading, eliminating the need for specialised equipment and significantly reducing the detection cost. This cost-effective approach carries the potential to expedite on-site and naked-eye I2 detection, opening up new possibilities for research and application.

Synthesis of pyrazole and 1,3,4-oxadiazole derivatives of pharmaceutical potential

Heterocyclic compounds are important molecules that serve as scaffolds or linkers for the core structure of numerous drug substances. In particular, pyrazole and 1,3,4-oxadiazole are compounds of great interest due to their comprehensive biological activities and interesting structural features. Here, we described an efficient and economical synthetic route leading to N-phenyl substituted pyrazole and 1,3,4-oxadiazole derivatives. Retrosynthetic disconnective analysis showed that the N-phenyl substituted pyrazole can be obtained from chalcone, accessible from the respective aldehyde, and acetophenone. The disubstituted 1,3,4-oxadiazole can be constructed from the respective aldehyde, which originates from pyrrole-containing compound, and formyl chloride. Based on our retrosynthetic analysis, N-phenyl substituted pyrazole was obtained by cyclization of the respective chalcone with phenylhydrazine to give pyrazoline which was in turn converted into pyrazole by oxidative aromatization. Potassium carbonate and a catalytic amount of molecular iodine were used to oxidatively cyclize semicarbazones into 1,3,4-oxadiazoles in a transition metal-free process. Novel pyrazole and 1,3,4-oxadiazoles with potential biological activity are investigated as antituberculosis, anticonvulsant, antidiabetic, anticancer, and tyrosinase inhibitory agents.

Optical Frequency References at 1542 nm: Precision Spectroscopy of the R(106)50-0, R(100)49-0, R(84)47-0, R(59)45-0, P(82)47-0, and P(71)46-0 Lines of 127I2 at 514 nm

Frequency-stabilized lasers are fundamental topics in research relating to optical frequency and wavelength standards. The absolute frequencies and hyperfine structures of the R(106)50-0, R(100)49-0, R(84)47-0, R(59)45-0, P(82)47-0, and P(71)46-0 lines of molecular iodine (127I2) at 514 nm were measured using a frequency-stabilized laser based on modulation transfer spectroscopy. The hyperfine splitting of each line was fitted to a four-term Hamiltonian with an uncertainty of several kilohertz to obtain the hyperfine constants for the line. A total of 97 hyperfine transitions of the six lines were measured with an uncertainty of 5.6 kHz (fractionally 9.6 × 10−12). They can provide new optical frequency references for telecommunication and other applications.

Spontaneous Production of I2 at the Surface of Aqueous Iodide Solutions.

Several groups have recently reported spontaneous production of atmospherically reactive species, including molecular iodine (I2) at the air-water interface of droplets. In this study, glancing angle laser-induced fluorescence spectroscopy was used to track the luminol fluorescence at the surface of sodium iodide (NaI) and sodium chloride (NaCl) solutions. Although luminol fluorescence is hardly quenched by halide anions, even up to fairly high concentrations, it is effectively quenched by I2. We observe luminol fluorescence quenching at the surface of NaI solutions but not at the surface of NaCl solutions, pointing to the formation of I2 at the surface of NaI solutions. This provides further support for the proposal that the strong electric field or the reduction solvation present at the air-water interface can initiate spontaneous iodide activation and other chemistry there. The spontaneous production of I2 at the surface of aqueous iodide solutions presents a previously unconsidered source of iodine in the atmosphere.

Molecular Iodine Improves the Efficacy and Reduces the Side Effects of Metronomic Cyclophosphamide Treatment against Mammary Cancer Progression.

Metronomic chemotherapy with cyclophosphamide (Cpp) has shown promising results in cancer protocols. These lower and prolonged doses have antiangiogenic, pro-cytotoxic, and moderate secondary effects. Molecular iodine (I2) reduces the viability of cancer cells and, with chemotherapeutic agents, activates the antitumoral immune response and diminishes side effects. The present work evaluates the adjuvant of oral I2 with Cpp using a murine model of mammary cancer. Female Sprague Dawley rats with 7,12-dimethylbenzantracene-induced tumors received Cpp intraperitoneal (50 and 70 mg/kg two times/week, iCpp50 and iCpp70) and oral (0.03%; 50 mg/Kg; oCpp50) doses. I2 (0.05%, 50 mg/100 mL) and oCpp50 were offered in drinking water for three weeks. iCpp70 was the most efficient antitumoral dose but generated severe body weight loss and hemorrhagic cystitis (HC). I2 prevented body weight loss, exhibited adjuvant actions with Cpp, decreasing tumor growth, and canceled HC mechanisms, including decreases in vascular endothelial growth factor (VEGF) and Survivin expression. oCpp50 + I2 diminished angiogenic signals (CD34, vessel-length, and VEGF content) and proinflammatory cytokines (interleukin-10 and tumor necrosis factor-alpha) and increased cytotoxic (lymphocytic infiltration, CD8+ cells, Tbet, and interferon-gamma) and antioxidant markers (nuclear erythroid factor-2 and glutathione peroxidase). I2 enhances the effectiveness of oCpp, making it a compelling candidate for a clinical protocol.

Pressure dependence of superconducting behavior of solid Br and I: A first-principles study

Based on the first-principles calculations, this study employs the HSE06 functional for the first time to understand the high-pressure behavior of diatomic molecular crystal bromine and iodine. It meticulously replicates the metallization process of iodine and bromine from aspects including bond length, charge density, band structure, and density of states. Furthermore, we also investigate the pressure-dependent superconducting properties of monoatomic phases of bromine and iodine, probing into the reasons behind the discrepancies in Tc values among different phases.

Synthesis and characterization of new highly fluorinated phosphoramidates bearing different alkylamino groups

Seventeen new highly fluorinated phosphoramidates containing alkylamino moieties of the type (RFO)2P(O)NHR (R = CH2CH2CH3, (CH2)3CH3, (CH2)4-CH3, CH(CH3)2, C6H11, CH2CH2-C6H5, CH2-C6H5 or C6H5; RF = CH2CF3, CH2C2F5 or CH2CH2C6F13) were synthesized. These compounds were obtained through the reaction of primary amines with bis(polyfluoroalkyl)phosphites as phosphorylating agents, using molecular iodine as a mild catalyst and in the presence of H2O2.This method was chosen out of various literature common methods, which were thoroughly investigated using 31P NMR spectroscopy. In addition, the variation in reaction rates among different phosphites was studied and compared with previous research findings.The title phosphoramidates were fully characterized using multinuclear (1H,13C,31P, and 19F) NMR, IR, and HRMS techniques.

Decarboxylative Iodination of Coumarin‐3‐carboxylic Acids: A Facile Access to 3‐Iodocoumarins

A straightforward protocol for the direct conversion of readily available coumarin‐3‐carboxylic acids to the corresponding 3‐iodocoumarins is described herein. Heating acetonitrile solution of coumarin‐3‐carboxylic acids, molecular iodine and potassium hydrogen phosphate resulted in the decarboxylative iodination of coumarin‐3‐carboxylic acids via radical mechanism. Various electron rich and electron poor coumarin‐3‐carboxylic acids were compatible with the established reaction conditions and consequently afforded the corresponding 3‐iodocoumarins in (46‐93%) reaction yields with minimum purification efforts. The formed products serve as valuable precursors to streamline more complex organic compounds incorporating coumarin core.