• Several pathways exist for the halogenation of organic compounds, including free radical halogenation, ketone halogenation, electrophilic halogenation, and halogen addition reaction. (wikipedia.org)
  • Aromatic compounds are subject to electrophilic halogenation: RC6H5 + X2 → HX + RC6H4X This reaction works only for chlorine and bromine and is carried in the presence of a Lewis acid such as FeX3 (laboratory method). (wikipedia.org)
  • Saturated hydrocarbons typically do not add halogens but undergo free radical halogenation, involving substitution of hydrogen atoms by halogen. (wikipedia.org)
  • In oxychlorination, the combination of hydrogen chloride and oxygen serves as the equivalent of chlorine, as illustrated by this route to dichloroethane: 2 HCl + CH2=CH2 + 1⁄2 O2 → ClCH2CH2Cl + H2O The facility of halogenation is influenced by the halogen. (wikipedia.org)
  • An example of alpha halogenation is the mono-bromination of acetone, carried out under either acidic or basic conditions, to give bromoacetone: Acidic (in acetic acid): Basic (in aqueous NaOH): In acidic solution, usually only one alpha hydrogen is replaced by a halogen, because each successive halogenation is slower than the first. (wikipedia.org)
  • A halogenation is either a substitution reaction in which one or more hydrogen atoms in an organic compound is replaced by halogen atoms or an addition reaction that introduces two or more halogen atoms to an organic compound. (ochempal.org)
  • Taking into account the effect of halogenation on hydrogen bonding is thus important when evaluating structural and/or energetic parameters of ligand-protein complexes. (jove.com)
  • Regioselective halogenation of organic compounds using non-toxic halide salts and oxygen in aqueous media at ambient temperatures - a tough task for conventional chemical synthesis. (rsc.org)
  • The regioselectivity also differs: The halogenation of an unsymmetrical ketone in acid results in the more substituted alkyl group being halogenated. (wikipedia.org)
  • The pathway and stoichiometry of halogenation depends on the structural features and functional groups of the organic substrate, as well as on the specific halogen. (wikipedia.org)
  • Subsequent halogenation (which usually cannot be stopped by control of stoichiometry) occurs at the position which already has a halogen substituent, until all hydrogens have been replaced by halogen atoms. (wikipedia.org)
  • In organic chemistry α-keto halogenation is a special type of halogenation. (wikipedia.org)
  • In chemistry, halogenation is a chemical reaction that involves the addition of one or more halogens to a compound or material. (wikipedia.org)
  • Using cyano as the directing group, a palladium-catalyzed ortho -halogenation (I, Br, Cl) reaction gave good to excellent yields. (organic-chemistry.org)
  • Inorganic compounds such as metals also undergo halogenation. (wikipedia.org)
  • It appears that the unmatched versatility of flavoenzymes is ideally suited for secondary metabolism, nature's biosynthetic tinkering ground, and significantly contributes to the vast chemical diversity of natural products via functionalization (e.g., halogenation, hydroxylation) or substrate activation reactions (e.g. dehydrogenation). (zbsa.de)
  • For the halogenation of 4-methoxybenzonitrile, there is a competition between the palladium-catalyzed ortho -halogenation and an electrophilic substitution (to form 3-halo-methoxybenzonitrile) due to the strong electron-donating property of the methoxyl group. (organic-chemistry.org)
  • Gold-catalysed halogenation was further combined with gold-catalysed hydration and subsequent annulation to provide convenient routes to iodomethyl ketones and five-membered aromatic heterocycles. (ucl.ac.uk)
  • Chemical halogenation requires harsh conditions, often employing elemental halogens in combination with Lewis acids. (iucr.org)
  • Free radical halogenation is used for the industrial production of chlorinated methanes: CH4 + Cl2 → CH3Cl + HCl Rearrangement often accompany such free radical reactions. (wikipedia.org)
  • All of the halogenation mechanism reactions occur very rapidly, and the formation of the products takes only microseconds. (cliffsnotes.com)
  • This learning unit describes the principles, kinetics, and thermodynamics of the radical halogenation of alkanes and it explains the reasons for the different chemical properties of the halogens fluorine, chlorine, bromine, and iodine in radical substitution reactions. (chemgapedia.de)
  • Well, for our purposes, halogenation of alkynes just about covers the important reactions for the 3-membered ring pathway of alkynes. (masterorganicchemistry.com)
  • Most halogenation reactions of hydrocarbons proceed via a free-radical chain reaction mechanism. (bartleby.com)
  • The regiochemistry of the halogenation of alkanes is usually determined by the relative weakness of the available C-H bonds. (wikipedia.org)
  • Radical halogenation of alkanes: principles, kinetics, and thermodynamics. (chemgapedia.de)
  • Here's a video on the halogenation of alkanes. (socratic.org)
  • The only reaction alkanes undergo is radical halogenation , the gateway to the rest of organic synthesis. (clutchprep.com)
  • Reactivity of alkanes: halogenation and oxidation. (unimi.it)
  • This chemical reaction mechanism drawing depicts steps of carbonyl compound halogenation reaction. (conceptdraw.com)
  • This sample shows the steps involved in a carbonyl compound halogenation reaction. (conceptdraw.com)
  • The pathway and stoichiometry of halogenation depends on the structural features and functional groups of the organic substrate, as well as on the specific halogen. (wikipedia.org)
  • What do the pathway and stoichiometry of halogenation depend on? (socratic.org)
  • In chemistry, halogenation is a chemical reaction that involves the addition of one or more halogens to a compound or material. (wikipedia.org)
  • In organic chemistry α-keto halogenation is a special type of halogenation. (wikipedia.org)
  • The chemical drawing example "Carbonyl compound halogenation mechanism" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Chemistry solution from the Science and Education area of ConceptDraw Solution Park. (conceptdraw.com)
  • In organic chemistry, halogenation is the reaction of a halogen with another substance in which a halogen atom ends up as part of that substance. (socratic.org)
  • Then the addition of HX to alkynes in comparison with the HX addition to alkenes and the halogenation of alkynes are described. (chemgapedia.de)
  • Several pathways exist for the halogenation of organic compounds, including free radical halogenation, ketone halogenation, electrophilic halogenation, and halogen addition reaction. (wikipedia.org)
  • Regioselective halogenation of organic compounds using non-toxic halide salts and oxygen in aqueous media at ambient temperatures - a tough task for conventional chemical synthesis. (rsc.org)
  • Why do organic compounds undergo halogenation much more often than inorganic compounds? (socratic.org)
  • An example of alpha halogenation is the mono-bromination of acetone, carried out under either acidic or basic conditions, to give bromoacetone: Acidic (in acetic acid): Basic (in aqueous NaOH): In acidic solution, usually only one alpha hydrogen is replaced by a halogen, because each successive halogenation is slower than the first. (wikipedia.org)
  • Of particular interest are bioactive compounds produced through the selective oxidation of fatty acids to eicosanoids and related oxylipins, or the selective halogenation of terpenoids to brominated/chlorinated monoterpenes [Carte, 1996]. (springer.com)
  • In the Hell-Volhard-Zelinsky halogenation, carboxylic acids are alpha-halogenated. (wikipedia.org)
  • Gold-catalysed halogenation was further combined with gold-catalysed hydration and subsequent annulation to provide convenient routes to iodomethyl ketones and five-membered aromatic heterocycles. (ucl.ac.uk)
  • A particularly common α-substitution reaction in the laboratory is the halogenation of aldehydes and ketones at their α positions by reaction Cl2, Br2 or I2 in acidic solution. (conceptdraw.com)
  • a) O xidation with Jones Reagent (Aldehydes) b) Bayer-Villiger o xidation (Ketones) b) En amine formation 4. (coursehero.com)
  • Industrial scale synthesis of chloromethane ( CH 3 Cl ) is achieved by gas-phase radical halogenation of methane with chlorine. (ucla.edu)
  • In the halogenation reaction of organic olefin compounds, an excess amount of halogen gas (fluorine, chlorine, vaporized bromine and iodine, or their combination) is normally used in order to achieve as complete as possible conversion of the organic starting material. (patents.com)
  • THE HALOGENATION OF ALKENES This page looks at the reaction of the carbon-carbon double bond in alkenes such as ethene with halogens such as chlorine, bromine and iodine. (thejeffreyfoundation.org)
  • A second equivalent of halogen results in the halogenation of the other alkyl substituent (without the halogen). (wikipedia.org)
  • Halogenation is a common modification employed in pharmaceutical studies that enables systematic variation is the electronic properties of the molecule of interest due to the availability of halogen substituents that vary in size, dipole moment, polarizability, and electron withdrawing properties. (illinois.edu)
  • Halogenation of alkenes is the reaction in which a double bond is broken and replaced by a vicinal dihalide - 2 halogen atoms added to neighboring carbons. (leah4sci.com)
  • 3. The method of claim 2, wherein said halogenation/reduction sequence comprises halogenation of the inorganic oxide substrate followed by reduction of the halogenated material and then post-reaction treatment with aqueous acid. (google.com)
  • Optimisation of enzymatic halogenation in reversed micelles. (wur.nl)
  • Enzymatic halogenation of apolar compounds using reversed micelles. (wur.nl)
  • A practical and efficient method for halogenation of activated carbon atoms using readily available N-haloimides and a Lewis acid catalyst has been disclosed. (patentsencyclopedia.com)
  • [0002] Halogenation of activated carbon atoms is a highly useful reaction for the synthesis of natural products and pharmaceutically important compounds. (patentsencyclopedia.com)
  • Two types of oxidative stress, peroxidation and halogenation stress, are gaining increasing importance as biochemical windows to a better understanding of the pathogenesis of this disease. (austinpublishinggroup.com)
  • Further halogenation can give dichloromethane ( methylene chloride ), trichloromethane ( chloroform ), and carbon tetrachloride . (ucla.edu)
  • Using cyano as the directing group, a palladium-catalyzed ortho -halogenation (I, Br, Cl) reaction gave good to excellent yields. (organic-chemistry.org)
  • For the halogenation of 4-methoxybenzonitrile, there is a competition between the palladium-catalyzed ortho -halogenation and an electrophilic substitution (to form 3-halo-methoxybenzonitrile) due to the strong electron-donating property of the methoxyl group. (organic-chemistry.org)
  • Herein, we describe an efficient, rapid and benign protocol for the direct C(sp 2 )-H bond halogenation (Cl, Br, I) of 2-arylimidazo[1,2- a ]pyridines using trihaloisocyanuric acids in ethanol. (rsc.org)
  • Halogenation stress is characterized by the excess of halogenated molecules such as hypohalous acids, haloamines and halogenated proteins. (austinpublishinggroup.com)
  • Free radical halogenation involves initiation, propagation, and termination steps. (socratic.org)
  • Why are the termination steps of free radical halogenation of low probability? (socratic.org)
  • The halogenation is a typical α-substitution reaction that proceeds by acid catalyzed formation of an enol intermediate. (conceptdraw.com)
  • First-principles calculations are employed to investigate structural, electronic and topological insulating properties of XBi (X = B, Al, Ga, and In) monolayers upon halogenation. (diva-portal.org)
  • Kinetic measurements have been made at 25 ° C on the halogenation of benzoylacetone, acetylacetone, ethyl acetoacetate, ethyl α-bromoacetoacetate and diethyl bromomalonate. (royalsocietypublishing.org)