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18-420: IBX can be prepared in a single step by adding an excess of Oxone to an aqueous solution of 2-iodobenzoic acid . After warming the solution to 70°C for three hours, the precipitated IBX is collected as a white crystalline solid (80% yield, ≥95% purity). Decomposition of IBX to 2-iodosobenzoic acid and 2-iodobenzoic acid occurs at elevated temperatures, and therefore purification by recrystallization from water

36-422: A class of organic compounds of the general form R−C(O)CH(OH)−R' , composed of a hydroxy group ( −OH ) adjacent to a ketone group ( >C=O ). The name acyloin is derived from the fact that they are formally derived from reductive coupling of carboxylic acyl groups ( −C(=O)OH ). They are one of the two main classes of hydroxy ketones , distinguished by the position of the hydroxy group relative to

54-689: A series of papers in the Journal of the American Chemical Society demonstrating, among other transformations, the use of IBX to oxidize primary and secondary benzylic carbons to aromatic aldehydes and ketones, respectively. IBX is notable for oxidizing vicinal diols (or glycols) to diketones without cleavage of the carbon-carbon bond, but oxidative cleavage of glycols to two aldehydes or ketones can occur when modified conditions are used (elevated temperatures or trifluoroacetic acid solvent). The reaction mechanism for this glycol cleavage

72-508: Is +1.81 V with a half reaction generating the hydrogen sulfate ( pH = 0 ): Potassium peroxymonosulfate per se is a relatively obscure salt, but its derivative called Oxone is of commercial value. Oxone refers to the triple salt 2KHSO 5 ·KHSO 4 ·K 2 SO 4 . As such about one third by weight is potassium peroxymonosulfate. Oxone has a longer shelf life than does potassium peroxymonosulfate. A white, water-soluble solid, Oxone loses <1% of its oxidizing power per month. Oxone, which

90-421: Is a requirement because the iodine to oxygen double bond is oriented out of plane with the alkoxy group and the concerted elimination would not be able to take place. This twist reaction is a rearrangement in which the oxygen atom is moved into a proper plane for a 5 membered cyclic transition state in the elimination reaction and is calculated by Computational chemistry to be the rate-determining step in

108-413: Is a versatile oxidant in organic synthesis. It oxidizes aldehydes to carboxylic acids ; in the presence of alcoholic solvents, the esters may be obtained. Internal alkenes may be cleaved to two carboxylic acids (see below), while terminal alkenes may be epoxidized . Sulfides give sulfones , tertiary amines give amine oxides , and phosphines give phosphine oxides . Further illustrative of

126-506: Is also available as silica gel or polystyrene bound IBX. In many applications, IBX is replaced by Dess–Martin periodinane which is more soluble in common organic solvents. A sample reaction is an IBX oxidation used in the total synthesis of eicosanoid : More and Finney and Van Arman have demonstrated that common organic solvents are suitable for many IBX oxidations, despite its low solubility, and in fact may simplify product purification. In 2001, K. C. Nicolaou and co-workers published

144-411: Is based on initial formation of an adduct between 10-I-4 IBX and DMSO to a 12-I-5 intermediate 3 in which DMSO acts as a leaving group for incoming alcohol 4 to intermediate 5 . One equivalent of water is split off forming 12-I-5 spirobicyclic periodinane 6 setting the stage for fragmentation to 7 . With hydroxyl alpha protons present, oxidation to the acyloin competes. Trifluoroacetic acid

162-426: Is commercially available, is produced from peroxysulfuric acid, which is generated in situ by combining oleum and hydrogen peroxide . Careful neutralization of this solution with potassium hydroxide allows the crystallization of the triple salt. Oxone is used widely for cleaning. It whitens dentures, oxidizes organic contaminants in swimming pools, and cleans chips for the manufacture of microelectronics. Oxone

180-509: Is found to facilitate the overall reaction. Kirsch and co-workers were able to hydroxylate keto compounds with IBX in α-position under mild conditions. This method could be extended to β-keto esters. Bartlett and Beaudry discovered that IBX is a valuable reagent for the transformation of β-hydroxyketones to β-diketones. IBX provides yields superior to both the Swern and Dess–Martin oxidation protocols. Oxone Potassium peroxymonosulfate

198-415: Is not possible. Purity can be increased (≥99%) by shorting the reaction time to one hour at 70°C, at the cost of slightly reducing yield to 77%. The reaction mechanism for an oxidation of an alcohol to an aldehyde according to the hypervalent twisting mechanism involves a ligand exchange reaction replacing the hydroxyl group by the alcohol followed by a twist and an elimination reaction . The twist

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216-412: Is replaced by a methyl group thus facilitating the twist until the elimination reaction takes prevalence as the rate determining step. IBX exists as two tautomers , one of which is the carboxylic acid . The acidity of IBX which has been determined in water ( pKa 2.4) and DMSO (pKa 6.65) is known to affect organic reactions, for instance acid-catalyzed isomerization accompanying oxidations. IBX

234-408: Is widely used as an oxidizing agent , for example, in pools and spas (usually referred to as monopersulfate or "MPS"). It is the potassium salt of peroxymonosulfuric acid . Potassium peroxymonosulfate per se is rarely encountered. It is often confused with the triple salt 2KHSO 5 ·KHSO 4 ·K 2 SO 4 , known as Oxone . The standard electrode potential for potassium peroxymonosulfate

252-588: The epoxidation of olefins . Dioxiranes are also oxidize other unsaturated functionality, heteroatoms, and alkane C-H bonds. Oxone has been investigated for the delignification of wood. Ammonium , sodium , and potassium salts of H are used in the plastics industry as radical initiators for polymerization . They are also used as etchants , oxidative desizing agents for textile fabrics, and for decolorizing and deodorizing oils. Acyloin In organic chemistry , acyloins or α-hydroxy ketones are

270-433: The oxidative power of this salt is the conversion of an acridine derivative to the corresponding acridine- N-oxide . Oxone oxidizes sulfides to sulfoxides and then to sulfones . Oxone converts ketones to dioxiranes , which are used for diverse oxidations in organic synthesis. The dominant reagent dimethyldioxirane (DMDO) forms upon treatment of acetone with oxone. Dioxiranes are versatile, especially for

288-399: The ketone; in this form, the hydroxy is on the alpha carbon , explaining the secondary name of α-hydroxy ketone . Classic organic reactions exist for the synthesis of acyloins. When sulfonyloxaziridines oxidize enol(ate)s, the latter reacts by nucleophilic displacement at the electron deficient oxygen of the oxaziridine ring. This reaction type is extended to asymmetric synthesis by

306-444: The oxidation. The twist mechanism also explains why oxidation is faster for larger alcohols than for small alcohols. The twist is driven forward by the steric hindrance that exists between the ortho hydrogen atom and the protons from the alkoxy group and larger alkoxy groups create larger steric repulsion. The same computation predicts a much faster reacting IBX derivative with a 100 fold reaction rate when this ortho hydrogen atom

324-467: The use of chiral oxaziridines derived from camphor (camphorsulfonyl oxaziridine). Each isomer gives exclusive access to one of the two possible enantiomers . This modification is applied in the Holton taxol total synthesis . In the enolate oxidation of the cyclopentadienone below with either camphor enantiomer, the trans isomer is obtained because access for the hydroxyl group in the cis position

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