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Current decarboxylative halogenation methods typically require expensive or toxic transition metal catalysts and have limited solvent compatibility. Herein, we report a novel transition-metal-free and solvent-tolerant decarboxylative iodination method by using iodine monochloride in the presence of potassium phosphate, which are effective to readily available aryl and heteroaryl carboxylic acids, and can be executed in a variety of solvents, including water. [ABSTRACT FROM AUTHOR]

Iodine value is an essential parameter for assessing the composition and quality of oils. A commonly used method for iodine value determination is the Wijs method. Recently, the HPLC method for assay of iodine monochloride via iodination of 2-chloroaniline with iodine monochloride has been reported. This study presents an approach for iodine value determination by HPLC via quantification of the unreacted iodine monochloride after reaction with oil samples, similar to the back titration approach in the Wijs method. Chromatographic conditions consist of gradient elution using water and acetonitrile on the C18 column with a detection wavelength of 304 nm. Oleic acid, with a known iodine value (83–103 gI/100 g), was used as a method development and validation reference compound. The method was validated as per International Conference on Harmonization guidelines and was accurate (98–102%), robust, and linear (r2 = 0.999) for oleic acid ranging from 5 to 20 mg. The repeatability and intermediate precision were within 1%. The validated method was applied for the iodine value determination of 10 cold-pressed oils. Thus, an HPLC method is developed, which offers minimal sample requirements, high accuracy, less manual intervention, and precision for the iodine value determination of oils. [ABSTRACT FROM AUTHOR]

Quantum chemical computations at M06-2X/def2-TZVPD level of theory were employed to compute structural and thermodynamic properties of gaseous donor-acceptor complexes IX·LB [X = I, Cl; LB = trimethylamine, triethylamine, pyridine, 2-aminopyridine, 4,4′-bipyridine, pyrazine, 1,2-bis(4-pyridyl)ethylene, 1,2-bis(4-pyridyl)ethane]. Iodine monochloride is a stronger Lewis acid compared to the molecular iodine. With respect to homogeneous gas phase dissociation into components, the complex of ICl with triethylamine is the most stable and the complex of I2 with pyrazine is the least stable. It is shown that dissociation enthalpies do not correlate with proton affinity of the Lewis base, but there is a good correlation between dissociation enthalpies and I–X bond lengthening upon complex formation. This allows to estimate the stability of the complex based on its structural data. [ABSTRACT FROM AUTHOR]

Iodine monochloride is conventionally determined using the sodium thiosulphate titration method. Recently, mono‐iodination of 2‐chloroaniline in N,N‐dimethylformamide has been reported in the presence of iodine monochloride. A reversed‐phase high‐performance liquid chromatography method for the assay of iodine monochloride on the C18 column has been developed via the iodination of 2‐chloroaniline. Chromatographic separation was achieved using gradient elution with water and acetonitrile as mobile phase at 1 ml/min flow rate and detection at 304 nm. The elution of 2‐chloro‐4‐iodoaniline was observed at 5.492 min. Under the given experimental conditions, an excess of 2‐chloroaniline dissolved in acetonitrile reacted with a known amount of pure iodine monochloride resulting in 2‐chloro‐4‐iodoaniline. The amount of 2‐chloro‐4‐iodoaniline formed is a measure of the initial iodine monochloride concentration, thus providing the assay of iodine monochloride. The method was validated as per the guidelines of the International Conference on Harmonization guidelines and found to be linear (r2 = 0.999) and accurate (98%–102%) for iodine monochloride concentrations ranging from 0.4 to 1.2 mg/ml. The intra‐day and inter‐day precision were within 1%. The validated method was successfully applied to determine the assay of commercially available iodine monochloride, Wijs solution, and in‐situ generated iodine monochloride samples. Thus, a novel, simple, accurate, and precise HPLC method has been developed for iodination monochloride assay. [ABSTRACT FROM AUTHOR]

The efficient regioselective bromination and iodination of the nonsteroidal anti-inflammatory drug (NSAID) carprofen were achieved by using bromine and iodine monochloride in glacial acetic acid. The novel halogenated carprofen derivatives were functionalized at the carboxylic group by esterification. The regioselectivity of the halogenation reaction was evidenced by NMR spectroscopy and confirmed by X-ray analysis. The compounds were screened for their in vitro antibacterial activity against planktonic cells and also for their anti-biofilm effect, using Gram-positive bacteria (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212) and Gram-negative bacteria (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853). The cytotoxic activity of the novel compounds was tested against HeLa cells. The pharmacokinetic and pharmacodynamic profiles of carprofen derivatives, as well as their toxicity, were established by in silico analyses. [ABSTRACT FROM AUTHOR]

In this communication, we investigate the reaction between seleno- and thiourea, derived from N-heterocyclic carbenes, with the interhalogen iodine monochloride. The formation of all three products was confirmed by NMR spectroscopy, while single-crystal X-ray analyses were able to establish a charge-transfer coordination type, which showed a linear Se/S-I-Cl arrangement, for all adducts formed. Based on a detailed crystallographic analysis, we can deduce the zwitterionic character of these compounds. [ABSTRACT FROM AUTHOR]

In this communication, we investigate the reaction between seleno- and thiourea, derived from N-heterocyclic carbenes, with the interhalogen iodine monochloride. The formation of all three products was confirmed by NMR spectroscopy, while single-crystal X-ray analyses were able to establish a charge-transfer coordination type, which showed a linear Se/S-I-Cl arrangement, for all adducts formed. Based on a detailed crystallographic analysis, we can deduce the zwitterionic character of these compounds.

We present for the first time a coherent ab initio study of 39 states of valence, Rydberg, and ionpair character of the diatomic interhalogen ICl species through large scale multireference variational methods including spin-orbit effects coupled with quantitative basis sets. Various avoided crossings are responsible for a non-adiabatic behaviour creating a wonderful vista for its theoretical description. Our molecular constants are compared with all available experimental data with the aim to assist experimentalists especially in the high energy regime of up to ~95 000 cm-1 . [ABSTRACT FROM AUTHOR]

The efficient regioselective bromination and iodination of the nonsteroidal anti-inflammatory drug (NSAID) carprofen were achieved by using bromine and iodine monochloride in glacial acetic acid. The novel halogenated carprofen derivatives were functionalized at the carboxylic group by esterification. The regioselectivity of the halogenation reaction was evidenced by NMR spectroscopy and confirmed by X-ray analysis. The compounds were screened for their in vitro antibacterial activity against planktonic cells and also for their anti-biofilm effect, using Gram-positive bacteria (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212) and Gram-negative bacteria (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853). The cytotoxic activity of the novel compounds was tested against HeLa cells. The pharmacokinetic and pharmacodynamic profiles of carprofen derivatives, as well as their toxicity, were established by in silico analyses.

Graphene intercalation materials are potentially promising for the implementation of the ultra-low power, excitonic-condensate-based Bilayer pseudoSpin Field-Effect Transistor (BiSFETs) concept, as well as other novel device concepts requiring a graphene interlayer dielectric. Using density functional theory, we study the structural and electronic properties of bilayer graphene intercalated with iodine monochloride (ICl) and iodine monobromide (IBr). We determine the structural configuration of ICl and IBr graphene intercalation compounds (GICs). We also conduct an in-depth exploration of inter-layer electronic coupling, using ab initio calculations. The presence of intercalants dopes the graphene layer. It also reduces, but does not eliminate, the electronic coupling between graphene layers, which may enable BiSFET operation. In addition, we present experimental results for ICl-GIC synthesis and characterization. [ABSTRACT FROM AUTHOR]

We present slice imaging data demonstrating the influence of clustering on the photodissociation dynamics of a diatomic molecule: iodine monochloride (ICl) was dissociated at 235 nm in He and Xe seed gasses, probing both Cl and I photofragment energy and angular distributions. We observe that the kinetic energy releases of both Cl and I fragments change from He to Xe seeding. For Cl fragments, the seeding in Xe increases the kinetic energy release of some Cl fragments with a narrow kinetic energy distribution, and leads to some fragments with rather broad statistical distribution falling off exponentially from near-zero energies up to about 2.5 eV. Iodine fragment distribution changes even more dramatically from He to Xe seeding: sharp features essentially disappear and a broad distribution arises reaching to about 2.5 eV. Both these observations are rationalized by a simple qualitative cluster model assuming ICl dissociation inside larger xenon clusters and 'on surface' of smaller Xe species. [ABSTRACT FROM AUTHOR]

A metal‐free method for the construction of oxazolidine‐2,4‐diones and oxindoles was discussed. Using iodine monochloride (ICl) as both the reaction promoter and iodide source, the iodolactonization of N‐Boc acrylamides proceeded readily and provided the corresponding iodo oxazolidine‐2,4‐diones and oxazolidin‐2‐ones in good isolated yields. The obtained oxazolidine‐2,4‐diones can be used as key intermediates in the synthesis of toloxatone. When N‐alkyl‐N‐arylacrylamide derivatives were subjected to the same reaction, iodocarbocyclization products 3,3‐disubstituted oxindoles were obtained. The obtained oxindoles can be used as key intermediates in the synthesis of the alkaloids (±)‐esermethole and (±)‐physostigmine. A metal‐free method for the construction of oxazolidine‐2,4‐diones and oxindoles is reported herein. The resulting products can be used as key intermediates in synthesis of bioactive compounds such as toloxatone, (±)‐esermethole, and (±)‐physostigmine. [ABSTRACT FROM AUTHOR]

Gum arabic, a plant polysaccharide was oxidized with periodate to produce aldehyde groups by the cleavage of diols present in the sugar units. The oxidized gum was then iodinated with iodine monochloride (ICl) and the interaction between electrophilic iodine, I + and reactive carbonyl groups of the modified gum was studied.Results of titrimetric estimation performed to determine the extent of oxidation and aldehyde content in the oxidized gum showed that degree of oxidation ranged between 19.68–50.19% which was observed to increase with periodate concentration; the corresponding aldehyde content was calculated to be 5.15–40.42%. Different strengths of ICl were used to iodinate the oxidized gum and the iodine content of the complexes varied from 6.11–11.72% as determined by iodometric titration. Structure elucidation of the iodine complexes conclusively established the attachment of ICl molecules to CHO groups. A reaction scheme has been proposed suggesting an electrophilic addition of the reagent to the aldehyde groups, a mechanism that was also supported by iodide ion release studies. [ABSTRACT FROM AUTHOR]

A protocol has been developed to achieve selective and direct synthesis of α-iodoketones under mild condition, from the reaction of aminoalkynols with iodine monochloride. The scope of the reaction was investigated using various aminoalkynols with iodine monochloride and the corresponding α-iodoketones were obtained selectively without forming iodocyclized and/or addition products. [ABSTRACT FROM AUTHOR]

The electronic absorption spectra of aqueous solutions of iodine monochloride ICl are studied. The spectra of as-prepared solutions display the absorption band associated with hydrated ICl molecules. An additional band indicating that molecular iodine was formed in the solution emerges in the spectrum as dissolution takes place. Only the band belonging to iodine monochloride remains in the absorption spectra, and no additional bands appear after chloride anions Cl are added to the solution. The absorption spectrum becomes more complex when ICl is dissolved in an alkaline medium. The band belonging to molecular iodine emerges in the spectra at low alkali concentrations, while being transformed to other shorter-wavelength bands at high alkali concentrations (рН ≥ 12). [ABSTRACT FROM AUTHOR]

The reaction of the piperazine mono-adduct, N(CH2CH2)2NC60, with diiodine produced well ordered, black crystals of (I2N(CH2CH2)2NI2)C60·2.884(C6H6)·0.116I2, which contains two nearly linear N–I–I units. Reaction of N(CH2CH2)2NC60 with iodine monochloride produced two materials: the dihalogen adduct, (ClIN(CH2CH2)2NICl)C60·2.3(CS2)·0.7(CH2Cl2), when crystallization occurred rapidly from carbon disulfide/dichloromethane solution or the salt, [(N(CH2CH2)2NH)C60+][ICl2−]·CS2, when crystallization happened more slowly from toluene/dichloromethane solution where hydrolysis of the iodine monochloride by adventitious water presumably occurred. [ABSTRACT FROM AUTHOR]

Herein, we present some aspects regarding the iodination/bromination of 4-hydroxycoumarin or itsO-methyl orO-acetyl derivatives with iodine monochloride or iodine monobromide as halogenation reagents. Also, the investigation of photochemical transformation of the three 3-iodocoumarins was investigated for the first time. [ABSTRACT FROM AUTHOR]

The article offers information on chlorination of 3-arylsydnones with the application of iodine monochloride.

The structural and electronic properties of the global minimum structures of neutral, anionic and cationic CLi( n = 2-20; μ = 0, ±1) clusters were systematically investigated using the unbiased CALYPSO structure searching method in conjunction with density functional theory calculations at the B3LYP/6-311+G* level of theory. It was found that the ground-state structures of neural CLi clusters exhibit linear and planar configurations at n = 2 and 3, respectively, above which three-dimensional configurations are preferred with C and several Li atoms encapsulated into the Li cages. There were only minor differences in the structure between the neutral and charged CLi clusters, which is in accordance with the calculated results of ionization potential and electron affinity. However, the addition/removal of one electron to/from the neutral species had a significant effect on the stabilities of the resulting charged clusters. The averaged binding energy indicated that cationic CLi clusters show relatively higher stabilities. Pronounced odd-even alternations were observed in the fragmentation energy, second-order energy difference and HOMO-LUMO energy gaps. Finally, detailed chemical bonding of the CLi cluster was analyzed based on the AdNDP method, and static polarizabilities of CLi clusters are discussed. [ABSTRACT FROM AUTHOR]

Grindstone technique has been found to be a highly efficient for thiocyanation of aromatic and heteroaromatic compounds with Iodine mono chloride/KHSO4, Potassium metaperiodate/KHSO4. The methods offered selective thiocyanation of aromatic and heteroaromatic compounds in good yields with remarkable rate accelerations. The developed protocols under nonconventional (sonication and grindstone) methods are also promising compared with the existing procedures. [ABSTRACT FROM AUTHOR]

Grindstone technique has been found to be a highly efficient for thiocyanation of aromatic and heteroaromatic compounds with Iodine mono chloride/KHSO4, Potassium metaperiodate/KHSO4. The methods offered selective thiocyanation of aromatic and heteroaromatic compounds in good yields with remarkable rate accelerations. The developed protocols under nonconventional (sonication and grindstone) methods are also promising compared with the existing procedures. [ABSTRACT FROM AUTHOR]

This paper presents an efficient methodology for the synthesis of flavones via the oxidative cyclization of 2′-hydroxychalcones in the presence of iodine monochloride with DMSO under ultrasound irradiation. Ultrasonic irradiation enhances the cyclization reaction and leads to reduced reaction time at lower reaction temperatures while generating flavones with high yields. [ABSTRACT FROM AUTHOR]

A novel and convenient synthesis of 1-naphthaldehydes through iodine monochloride promoted cascade reactions of 1-phenylpent-4-yn-2-ols is presented. Compared with literature procedures, this new method has advantages such as simple operation procedure, mild reaction conditions, good efficiency, and excellent regio-selectivity. [ABSTRACT FROM AUTHOR]

Acetylated gum Arabic (AGA) derivatives with different degrees of substitution (DS 0.97-2.74) were synthesized using acetyl chloride and a base under varying reaction conditions. The AGA derivatives were obtained in the form of microspheres and thereafter stable iodine products were prepared by doping the microspheres with an iodinating agent, iodine monochloride (ICl). The reaction between electrophilic iodine and polar carbonyl groups was studied by FT-IR, 1 H-NMR, and UV-VIS spectroscopies. The products were also characterized by DSC, TGA and SEM studies. The incorporated iodine was released in aqueous medium as iodide ions (I − ). A reaction scheme has been proposed for the iodination and de-iodination of the gum derivatives. This work suggests that the iodine derivatives of modified gum Arabic could be used as a source of iodide ions which is the nutritional form of iodine. [ABSTRACT FROM AUTHOR]

Following a route described by Müllen et al. we improved the preparation of 1,2,3-tris(3″-iodobiphenyl-2′-yl)benzene ( 4). During the required iododesilylation with iodine monochloride the unexpected formation of a mono-chlorinated compound 6 as major product was observed, when an excess of the iodination reagent was employed. The reaction mechanism for the formation of this compound involving an oxidizing process is discussed. X-ray crystallography of the subsequent alkynylated product 7 proves the location of the chlorine atom at the central benzene ring. The related compound 5 was likewise investigated by X-ray analysis revealing a preferred solid-state conformation ('2-up-1-down') different from that of the chlorinated compound ('propeller' conformation). Compound 7 showed remarkable conformational dynamics in solution as observed by 1H NMR spectroscopy. Temperature-dependent measurements allowed the calculation of an energy difference of two major conformers of ca. 2 kJ/mol and a rotational barrier Δ Grot of ca. 77 kJ/mol. These values were convincingly confirmed by DFT calculations. A subsequent Sonogashira reaction of 4 with a suitable bipyridine derivative provided a unique trivalent bipyridine derivative. [ABSTRACT FROM AUTHOR]

Recent progress in electrophilic cyclizations has led to the development of many electrophilic cyclizing agents. Among them, iodine monochloride (ICl) has recently emerged as one of the most promising. In this Review, we highlight the advances in iodine monochloride mediated electrophilic cyclizations from 2000 to 2014. In addition, the different transformations of organoiodine compounds (the usual products of these electrophilic cyclizations) are discussed. [ABSTRACT FROM AUTHOR]

Iodine monochloride (ICl) was discovered to be a highly efficient, green oxidant, which can oxidize aldose hemiacetals, diarylmethanols, arylalkylmethanols, anddialkylmethanols to the corresponding aldose lactones, diarylmethanones, arylalkylmethanones, and dialkylmethanones, respectively, in high yields. ICl as a green, metal-free oxidant is characterized by mild reaction condition, short reaction time, good yield, and broad scope. [ABSTRACT FROM AUTHOR]

In a total residence time of three minutes, ibuprofen was assembled from its elementary building blocks with an average yield of above 90 % for each step. A scale-up of this five-stage process (3 bond-forming steps, one work-up, and one in-line liquid-liquid separation) provided ibuprofen at a rate of 8.09 g h−1 (equivalent to 70.8 kg y−1) using a system with an overall footprint of half the size of a standard laboratory fume hood. Aside from the high throughput, several other aspects of this synthesis expand the capabilities of continuous-flow processing, including a Friedel-Crafts acylation run under neat conditions and promoted by AlCl3, an exothermic in-line quench of high concentrations of precipitation-prone AlCl3, liquid-liquid separations run at or above 200 psi to provide solvent-free product, and the use of highly aggressive oxidants, such as iodine monochloride. The use of simple, inexpensive, and readily available reagents thus affords a practical synthesis of this important generic pharmaceutical. [ABSTRACT FROM AUTHOR]