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Alcohol Oxidation
Alcohol oxidation is a collection of redox, oxidation reactions in organic chemistry that convert Alcohol (chemistry), alcohols to Aldehyde, aldehydes, Ketone, ketones, Carboxylic acid, carboxylic acids, and Ester, esters. The reaction mainly applies to primary and secondary alcohols. Secondary alcohols form ketones, while primary alcohols form aldehydes or carboxylic acids. A variety of oxidants can be used. Almost all industrial scale oxidations use oxygen or air as the oxidant. Through a variety of mechanisms, the removal of a hydride equivalent converts a primary or secondary alcohol to an aldehyde or ketone, respectively. The oxidation of primary alcohols to carboxylic acids normally proceeds via the corresponding aldehyde, which is transformed via an aldehyde hydrate (''gem''-diol, R-CH(OH)2) by reaction with water. Thus, the oxidation of a primary alcohol at the aldehyde level without further oxidation to the carboxylic acid is possible by performing the reaction in absenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redox
Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. The oxidation and reduction processes occur simultaneously in the chemical reaction. There are two classes of redox reactions: * Electron transfer, Electron-transfer – Only one (usually) electron flows from the atom, ion, or molecule being oxidized to the atom, ion, or molecule that is reduced. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * Atom transfer – An atom transfers from one Substrate (chemistry), substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously, the oxidation state of oxygen decreases as it accepts electrons r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propylene
Propylene, also known as propene, is an unsaturated organic compound with the chemical formula . It has one double bond, and is the second simplest member of the alkene class of hydrocarbons. It is a colorless gas with a faint petroleum-like odor. Propylene is a product of combustion from forest fires, cigarette smoke, and motor vehicle and aircraft exhaust. It was discovered in 1850 by A. W. von Hoffmann's student Captain (later Major General) John Williams Reynolds as the only gaseous product of thermal decomposition of amyl alcohol to react with chlorine and bromine. Production Steam cracking The dominant technology for producing propylene is steam cracking, using propane as the feedstock. Cracking propane yields a mixture of ethylene, propylene, methane, hydrogen gas, and other related compounds. The yield of propylene is about 15%. The other principal feedstock is naphtha, especially in the Middle East and Asia. Propylene can be separated by fractional distill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jones Reagent
Jones or Joneses may refer to: People and fictional characters *Jones (surname), a common Welsh and English surname * List of people with surname Jones, including fictional characters **Justice Jones (other) ** Judge Jones (other) *Jones (singer), a British singer-songwriter * Jones of Faerdref Uchaf, a Welsh noble family * Generation Jones, the generation of people born between 1954 and 1965 * Jones (''Animal Farm''), a human character in George Orwell's novel ''Animal Farm'' Places * Jones (Martian crater), an impact crater on Mars * Jones, Ontario, Canada * Jones, Isabela, Philippines *Banton, Romblon, Philippines (formerly as ''Jones'') United States * Jones, Alabama * Jones, Illinois * Jones, Kentucky * Jones, Michigan * Jones, Oklahoma *Jones, West Virginia *Jones Township (other) Arts and entertainment * "Jones" (''Law & Order: Criminal Intent''), an episode of the TV series *"Jones", a song from the album '' Certain Things Are Likely'' by Kissi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridinium Chlorochromate
Pyridinium chlorochromate (PCC) is a yellow-orange salt (chemistry), salt with the chemical formula, formula [C5H5NH]+[CrO3Cl]−. It is a reagent in organic synthesis used primarily for organic redox reaction, oxidation of Alcohol (chemistry), alcohols to form carbonyls. A variety of related compounds are known with similar reactivity. PCC offers the advantage of the selective oxidation of alcohols to aldehydes or ketones, whereas many other reagents are less selective. Structure and preparation PCC consists of a pyridinium cation, [C5H5NH]+, and a tetrahedral chlorochromate anion, [CrO3Cl]−. Related salts are also known, such as 1-butylpyridinium chlorochromate, [C5H5N(C4H9)][CrO3Cl] and potassium chlorochromate. PCC is commercially available. Serendipity, Discovered by accident, the reagent was originally prepared via addition of pyridine into a cold solution of chromium trioxide in concentrated hydrochloric acid: :C5H5N + HCl + CrO3 → [C5H5NH][CrO3Cl] In one alternative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridinium Dichromate
The Cornforth reagent (pyridinium dichromate or PDC) is a pyridinium salt of dichromate with the chemical formula 5H5NHsub>2 r2O7 This compound is named after the Australian-British chemist Sir John Warcup Cornforth (b. 1917) who introduced it in 1962. The Cornforth reagent is a strong oxidizing agent which can convert primary and secondary alcohols to aldehydes and ketones respectively. In its chemical structure and functions it is closely related to other compounds made from hexavalent chromium oxide, such as pyridinium chlorochromate and Collins reagent. Because of their toxicity, these reagents are rarely used nowadays. Synthesis and properties The Cornforth reagent is prepared by slow addition of a concentrated aqueous solution of chromium trioxide to pyridine. The reaction may cause explosion, which is avoided by thoroughly dissolving the trioxide in water and cooling the solution by ice. The product is filtered, washed with acetone and dried, yielding an orange powder. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridinium
Pyridinium refers to the cation . It is the conjugate acid of pyridine. Many related cations are known involving substituted pyridines, e.g. picolines, lutidines, collidines. They are prepared by treating pyridine with acids. As pyridine is often used as an organic base in chemical reactions, pyridinium salts are produced in many acid-base reactions. Its salts are often insoluble in the organic solvent, so precipitation of the pyridinium leaving group complex is an indication of the progress of the reaction. Pyridinium cations are aromatic, as determined through Hückel's rule. They are isoelectronic with benzene. ''N''-Alkylpyridinium cations When the acidic proton is replaced by alkyl, the compounds are called ''N''-alkylpyridinium. A simple representative is ''N''-methylpyridinium (). These pyridinium intermediates have been used as electrophiles in synthetic organic chemistry to build dearomatized congeners called dihydropyridines, as demonstrated in one example from Smit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collins Reagent
Collins reagent is the complex of chromium(VI) oxide with pyridine in dichloromethane. This metal-pyridine complex, a red solid, is used to oxidize primary alcohols to the corresponding aldehydes and secondary alcohols to the corresponding ketones. This complex is a hygroscopic orange solid. Synthesis and structure The complex is produced by treating chromium trioxide with pyridine. The complex is diamagnetic. According to X-ray crystallography, the complex is 5-coordinate with mutually trans pyridine ligands. The Cr-O and Cr-N distances are respectively 163 and 215 picometers. In terms of history, the complex was first produced by Sisler et al. Reactions Collins reagent is especially useful for oxidations of acid sensitive compounds. Primary and secondary alcohols are oxidized respectively to aldehydes and ketones in yields of 87-98%. Like other oxidations by Cr(VI), the stoichiometry of the oxidations is complex because the metal undergoes 3e reduction and the su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarett Oxidation
The Sarett oxidation is an organic reaction that oxidizes primary and secondary alcohols to aldehydes and ketones, respectively, using chromium trioxide and pyridine. Unlike the similar Jones oxidation, the Sarett oxidation will not further oxidize primary alcohols to their carboxylic acid form, neither will it affect carbon-carbon double bonds. Use of the original Sarett oxidation has become largely antiquated however, in favor of other modified oxidation techniques. The unadulterated reaction is still occasionally used in teaching settings and in small scale laboratory research. History First appearance The reaction is named after the American chemist Lewis Hastings Sarett (1917–1999). The first description of its use appears in a 1953 article co-authored by Sarett that relates to the synthesis of adrenal steroids. The paper proposes the use of the pyridine chromium complex CrO3-2C5H5N to oxidize primary and secondary alcohols. The complex would later become known as t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcohol Oxidation To Carbonyls
Alcohol may refer to: Common uses * Alcohol (chemistry), a class of compounds * Ethanol, one of several alcohols, commonly known as alcohol in everyday life ** Alcohol (drug), intoxicant found in alcoholic beverages ** Alcoholic beverage, an alcoholic drink * Rubbing alcohol, for sanitation and to kill germs Music * "Alcohol", a song by Barenaked Ladies from the 1998 album ''Stunt'' * "Alcohol", a song by Beck from the 1993 single " Loser" * "Alcohol" (Brad Paisley song), 2005 * "Alcohol", a song by Butthole Surfers from the 1993 album '' Independent Worm Saloon'' * "Alcohol", a song by CSS from the 2005 album ''Cansei de Ser Sexy'' * "Alcohol", a song by Gang Green from the 1986 album ''Another Wasted Night'' * "Alcohol", a song by Gogol Bordello from the 2007 album '' Super Taranta!'' * "Alcohol", a song by the Kinks from the 1977 album ''Muswell Hillbillies'' and ''Everybody's in Show-Biz'' * "Alcohol", a song by Millionaires, 2008 * "Alcohol", a song by Terminaator from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzyl
In organic chemistry, benzyl is the substituent or molecular fragment possessing the structure . Benzyl features a benzene ring () attached to a methylene group (). Nomenclature In IUPAC nomenclature, the prefix benzyl refers to a substituent, for example benzyl chloride or benzyl benzoate. Benzyl is not to be confused with phenyl with the formula . The term benzylic is used to describe the position of the first carbon bonded to a benzene or other aromatic ring. For example, is referred to as a "benzylic" carbocation. The benzyl free radical has the formula . The benzyl cation or phenylcarbenium ion is the carbocation with formula ; the benzyl anion or phenylmethanide ion is the carbanion with the formula . None of these species can be formed in significant amounts in the solution phase under normal conditions, but they are useful referents for discussion of reaction mechanisms and may exist as reactive intermediates. Abbreviations Benzyl is most commonly abbreviated Bn. F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allyl
In organic chemistry, an allyl group is a substituent with the structural formula . It consists of a methylene bridge () attached to a vinyl group (). The name is derived from the scientific name for garlic, . In 1844, Theodor Wertheim isolated an allyl derivative from garlic oil and named it "". The term allyl applies to many compounds related to , some of which are of practical or of everyday importance, for example, allyl chloride. Allylation is any chemical reaction that adds an allyl group to a Substrate (chemistry), substrate. Nomenclature A site adjacent to the unsaturated carbon atom is called the allylic position or allylic site. A group attached at this site is sometimes described as allylic. Thus, "has an allylic hydroxyl group". Allylic Carbon–hydrogen bond, C−H bonds are about 15% weaker than the C−H bonds in ordinary Orbital hybridisation, sp3 carbon centers and are thus more reactive. Benzylic and allylic are related in terms of structure, bond strength ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclohexanol
Cyclohexanol is the organic compound with the formula HOCH(CH2)5. The molecule is related to cyclohexane by replacement of one hydrogen atom by a hydroxyl group. This compound exists as a deliquescent colorless solid with a camphor-like odor, which, when very pure, melts near room temperature. Millions of tonnes are produced annually, mainly as a precursor to nylon.Michael Tuttle Musser "Cyclohexanol and Cyclohexanone" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. Production Cyclohexanol is produced by the oxidation of cyclohexane in air, typically using cobalt catalysts: :2 C6H12 + O2 → 2 C6H11OH This process coforms cyclohexanone, and this mixture ("KA oil" for ketone-alcohol oil) is the main feedstock for the production of adipic acid. The oxidation involves radicals and the intermediacy of the hydroperoxide C6H11O2H. Alternatively, cyclohexanol can be produced by the hydrogenation of phenol: :C6H5OH + 3 H2 → C6H11OH This process can al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
