Aromatic Iodination Research Articles

Prediction of reforming catalyst stability

The authors demonstrate the feasibility of predicting reforming catalyst activity from the results of tests under mild conditions. The experiments were performed in pilot units with circulating hydrogen-rich gas. The authors determined the contents of aromatic and olefinic hydrocarbons in the reformate. The test time under mild conditions was 100-120 h. Typical results are presented of the timewise change in content of aromatic hydrocarbons and iodine number under mild and severe conditions. The difference between the contents of aromatic hydrocarbons in the reformates obtained 20 and 100 h from the start of tests under severe conditions were used as a measure of the catalyst stability.

ChemInform Abstract: IODINATION OF BENZENE WITH IODINE AND METAL SALTS IN ACIDIC SOLVENTS

AbstractUnter der gegebenen Versuchsbedingung läßt sich Benzol (I) in sehr guter Ausb. zu lodbenzol (II) iodieren.

Iodination of Benzene with Iodine and Metal Salts in Acidic Solvents

Abstract Iodobenzene was obtained by a reaction of benzene with molecular iodine in trifluoromethanesulfonic acid in oxygen atmosphere in the presence of vanadium salt as a catalyst. The method affords a new aromatic iodination process in which benzene is iodinated directly with molecular iodine.

Aromatic chlorination and iodination of 8-methylquinoline. Benzyl bromination of 5-halo-8-methylquinolines

5-Chloro- and 5-iodo-8-methylquinoline were obtained by chlorination or iodination of 8-methylquinoline with chlorine or iodine in concentrated sulfuric acid in the presence of silver sulfate. 5-Fluoro-8-methylquinoline was synthesized from 5-amino-8-methylquinoline. 5-Chloro-, 5-bromo-, and 5-fluoro-8-methylquinoline were converted to the corresponding 5-halo-8-(bromomethyl)quinolines by bromination with N-bromosuccinimide. Partial displacement of iodine by bromine to give a mixture of 5-bromo- and 5-iodo-8-(bromomethyl)quinoline occurs in the analogous bromination of 5-iodo-8-methylquinoline.

In situ synthesis of aromatic iodine compounds for gas chromatograpic retention measurements

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTIn situ synthesis of aromatic iodine compounds for gas chromatograpic retention measurementsVeluppillai. Paramasigamani and Walter A. AueCite this: Anal. Chem. 1980, 52, 2, 373–375Publication Date (Print):February 1, 1980Publication History Published online1 May 2002Published inissue 1 February 1980https://doi.org/10.1021/ac50052a045RIGHTS & PERMISSIONSArticle Views28Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (376 KB) Get e-Alerts Get e-Alerts

Some reactions of copper(I) pentafluorothiophenolate as a nucleophile

Abstract Several aromatic compounds containing one or two C6F5S groups have been prepared by nucleophilic displacement reactions using CuSC6F5 in DMF solution. Aromatic iodine or bromine, rather than chlorine of fluorine is replaced by the SC6F5 group using CuSC6F5. A mechanism is postulated. New compounds prepared include p -(C6F6F5S)2C6H4, o - and m -(C6F5S)2C6F4 and p XC6H4SC6F5(X=C1, NO2, I, CH3, CO2C2H5).

Reactions of silver(I) acetate–iodine and thallium(I) acetate–iodine with substituted cyclopropanes

Treatment of phenylcyclopropane with silver(I) acetate–iodine or thallium(I) acetate–iodine gives, as the major products, 1,3-disubstituted phenylpropanes resulting from cyclopropane ring opening, and in some cases, from solvolysis of intermediate iodo-acetates. Similar products are given with silver(I) trifluoroacetate–iodine but in this case aromatic iodination also occurs. Treatment of norcarane with the same reagents also results in ring opening, but here secondary products result from elimination and subsequent addition. Both substrates are less reactive than alkenes towards each reagent. Reaction mechanisms are discussed. The action of other reagent systems involving electrophilic iodine with phenylcyclopropane and norcarane is reported.

Electrophilic additions of iodonium nitrate to unsaturated substrates

Iodonium nitrate (generated by reaction of iodine chloride with silver nitrate in chloroform–pyridine) reacts with a variety of unsaturated substrates to form the following: 1,4-conjugate addition products of the type alkenyl pyridinium nitrates; alkyliodopyridinium nitrates; products of aromatic iodination of both phenols and anilines; substituted benzodihydrofurans; tetrahydrofurans and tetrahydropyrans; polycyclic bridged ethers; lactones; thiazolines.

Scope and mechanism of aromatic iodination with electrochemically generated iodine(I)

Scope and mechanism of aromatic iodination with electrochemically generated iodine(I)

Untersuchung der Reaktionen von organischen Jodverbindungen mit feinst auf amorpher Kiesels�ure verteiltem Silbernitrat

The reactions are presented which take place between primary, secondary and tertiary alkyl iodides, alicyclic and aromatic iodine compounds on the one hand and very finely distributed AgNO3 on amorphous silicic acid on the other hand.

The Iodination of Benzene with Iodine in the Thallium(III) Trifluoroacetate-Trifluoroacetic Acid System

Abstract Molecular iodine in the system of thallium(III) trifluoroacetate-trifluoroacetic acid has been found to possess a high potency for aromatic iodination. Under controlled conditions, benzene and also mesitylene were stepby-step mono-, di-, and triiodinated, whereupon whole iodine was consumed for the iodination by the oxidation process of the thallium(III) salt. In the course of the iodination of benzene, an intermediate has been revealed to consist of thalliated benzenes, which were transformed into iodinated benzenes by the electrophilic attack of iodine.

New Applications of Periodic Acid and Periodates in Organic and Bio-Organic Chemistry

Recent applications of periodic acid and periodates to organic and bio-organic chemistry are reviewed. Unique periodate oxidations and synthetic methods employing periodates are discussed. 1. Properties of Periodates and Periodate Oxidation Mechanism 2. Condensed Aromatic Compounds 3. Nonbenzenoid Aromatics and Cyclopolyenes 4. Steroids 5. Periodic Acid as a New Oxidant for the Degradation of Bile Pigments 6. Heterocyclic Compounds (Indole and Tryptophan Derivatives) 7. Terpenes 8. Aromatic Iodination 9. Organic Salts of Periodic Acid 10. Synthesis of Heterocyclic Compounds 11. Stereospecific, Asymmetric Synthesis of Carbohydrates 12. Sulfur Compounds 13. Periodate as a Co-oxidant 14. Amines and Hydrazine Derivatives 15. Hydroxylamine Derivatives 16. Oxidation of Phenols, Benzenediols, Benzenehexols, and Hydroxy Aromatics 17. Flavanols 18. Fatty Acids 19. The Structure of Addition Polymers 20. Bio-organic Applications of Periodates 21. Other Periodate Applications 22. Miscellaneous Recent Results

Mechanism of iodination of some substituted thiophens

The mechanism of aromatic iodination proposed previously has been confirmed by a study of the reactions of substituted thiophens. For 2-phenylthiophen the kinetic hydrogen isotope effect depends upon the substrate concentration, which is consistent with the reaction scheme.

Preparation of 131I-labelled m-iodohippuric acid and its behaviour in kidney function studies compared to o-iodohippuric acid

A new technique for iodine labelling of aromatic iodine compounds is described and applied to the preparation of 131I-labelled m-iodohippuric acid ( m-IHA). Being stored in saline solution, labelled m-IHA is more stable with respect to formation of free radioiodide than o-iodohippuric acid ( o-IHA). Detailed animal experiments in rats and dogs lead to the conclusion that there are no significant differences in the behaviour of o-IHA and mIHA.

Iodination and iodo-compounds. Part IV. The effect of substituents and solvent composition on the rate of aromatic iodination by means of the tri-iodine cation

The rate and products of the reaction between each of a range of deactivated substituted benzenes and the tri-iodine cation, in sulphuric acid solution, have been investigated. The rate constants may be correlated by the electrophilic substituent constants σ+ giving a value for the reaction constant ρ=–6·4. The kinetic isotope effect for the iodination of benzoic acid was found to be kH/kD= 2. Further details of the solvent effect are reported.

Mechanism of aromatic iodination

Mechanism of aromatic iodination

Mechanism of aromatic iodination by iodine and nitric acid

Kinetics of the iodination of a number of substituted benzenes by iodine and nitric acid in acetic acid solution have been studied. The reaction is catalysed by dinitrogen tetroxide and hydrogen ions and evidence is presented to show that the iodinating species is protonated NO2I, which reacts in a slow step with the aromatic compound. Acidity function data for nitric acid in 10% aqueous acetic acid are presented and charge-transfer complex formation between iodine and m-xylene in acetic acid has been studied.

Base catalysis in aromatic iodination. Kinetics and mechanism of the iodination of p-cresol, 2,6-dimethylphenol, imidazole and dimethylaminobenzenesulfonic acid

Kinetics of the iodination of p-cresol, 2,6-dimethylphenol, imidazole and dimethylaminobenzenesulfonic acid in aqueous solutions was studied using various bases as a catalyst. For the reactions showing an isotope effect (i.e. with the phenols and imidazole), the acceleration seems to follow the “nucleophilicities” somewhat better than the basicities of the bases applied. However, in the iodination of dimethylaminobenzenesulfonic acid, a reaction in which no isotope effect is observed, the catalytic action appears to be proportional to the basicities. This may be caused by the occurrence of an iodinating agent BI 2.

Anodically initiated aromatic iodination and side chain substitution reactions

Anodically initiated aromatic iodination and side chain substitution reactions

Iodination and iodo-compounds. Part II. The kinetics of aromatic iodination by means of the tri-iodine cation

The reactions in sulphuric acid solutions between the tri-iodine cation and deactivated aromatic compounds follow second-order kinetics, first-order in each reagent. The rate of iodination varies with the concentration of water in the solvent and there is a moderately large kinetic isotope effect. The results are consistent with the occurrence of a two-stage reaction in which the loss of the proton is catalysed by the hydrogen sulphate ion.