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Hypohalites metal

Other oxoacid salts of the alkali metals are discussed in later chapters, e.g. borates (p. 205), silicates (p. 347), phosphites and phosphates (p. 510), sulfites, hydrogensulfates, thiosulfates, etc. (p. 706) selenites, selenates, tellurites and tellurates (p. 781), hypohalites, halites, halates and perhalates (p. 853), etc. [Pg.90]

This section concludes with a reminder that, in addition to the hypohalous acids HOX and metal hypohalites M(OX) , various covalent (molecular) hypohalites are known. Hypochlorites are summarized in Table 17.22. All are volatile liquids or gases at room temperature and are discussed elsewhere (see Index). Organic hypohalites are unstable and rapidly expel HX or RX to form the corresponding aldehyde or ketone ... [Pg.859]

Hydrogen peroxide has been shown to oxidize halide ions to halogens or positive halogen species in the presence of a metal catalyst. The generated halogens/hypohalites can then oxidize hydrocarbons to form alkyl or aryl halides. [Pg.572]

The finely divided metal is soluble in hypohalites if an excess of alkali is present. At red heat, the metal combines with C z to form the dichlondc. Ruthenium(VIIl) oxide is formed when an alkaline ruthenium solution is treated with a strong oxidant, such as chlorine, or bromate ion when the Ru is in acid solution,... [Pg.1453]

Acyl hypohalites are usually prepared in situ by reaction of a metal salt of die carboxylic acid widi a halogen (equation 3). Classically the silver salt is used, but problems associated widi die preparation of dry silver carboxylates, as well as the more obvious economic factor, have led to the development of methods using mercury and thallium salts. Evidently, those functional groups which react readily widi halogens are not compatible with this approach. A major limitation of the acyl hypohalites is the readiness with which they transfer halogen atoms to alkyl radicals this property essend ly limits their use to decarboxylative halogenation reactions. [Pg.718]

Diazo compounds Diazonium sulfides and derivatives, Xanthates 1,2-epoxides Halo-aryl metals Haloarenemetal tc-complexes Halogen oxides Hydrazinium salts Hypohalites... [Pg.2068]

The addition of silver or mercury oxide precipitates the metal halide, leaving behind the aqueous solution, which is very reactive and is used for bleaching and sterilizing purposes. Solutions of hypohalites can be made by introducing the appropriate halogen into basic solutions (equation 113), but these will also contain some halide anions. To obtain pure hypochlorites, it is necessary to carefully neutralize pure hypochlorous acid. The most stable hypochlorites are those of Li, Ca, Sr, and Ba, although some others are also known but are not as stable, or are not sufficiently pure. [Pg.754]

Perfluoroalkoxide ions are postulated as intermediates in the mechanism leading to the hypohalites from acid fluorides. Generally, organic hypofluorites can be prepared from acid fluorides by the action of metal fluorides and elemental fluorine (equation 52). ... [Pg.1347]

The route to 4-2 outlined here is unlikely to be profitable, because oxidation of Itydrazine leads to diimide, HNNH, rather than the dihydroxy hydrazine 4-4 [49], Precursor 4-3 is appeahng because it might be possible to photochemically extrade the very stable molecule benzene from it, providing 4. However, the bicyclic precursor to 4-5 suffers from the same kind of synthetic problem as 4-4. Indeed, organic compounds with N-O bonds are uncommon, and the synthesis of 4-2 or 4-3 may require some audacity. One unorthodox approach would be the reaction of a hydrazine metal salt ( rather inaccessible species [50]) with an acyl hypohalite [51], e.g. (surprisingly, 4-6 seems to be unknown) ... [Pg.181]

Halogenations are also strongly catalyzed by certain other metal ions. A well-studied case is catalysis by mercuric ion. In solutions of halogen and mercuric carboxylate salts, the dominant halogenating agents is the acyl hypohalite. The... [Pg.261]

Some chemical processes require the use of hazardous materials or heavy metals. Oxidations of alcohols into carbonyl compounds or carboxylic acids were frequently performed using either chromic acid or potassium permanganate. However, these two oxidants are derived from heavy metals, which are toxic and hence environmentally hazardous. Safe disposal of salts of these metals thus presents a considerable environmental concern. Fortunately, hypohalites may also be used to oxidize alcohols into carbonyl compounds and carboxylic acids, as exemplified in the procedures in Section 16.2.This oxidation procedure exemplifies green chemistry because the hypohalites are reduced to water and halide ion, which has little environmental impact. [Pg.561]

The alkaline-metal ion oxidations of reducing carbohydrates are useful as analytical methods, when carefully standardized, to detect and quantitatively determine reducing sugars. They, however, produce a number of oxidized carbohydrate products, including the onic acids, a-keto onic acids, and other degradation products. They, therefore, are not useful for the preparation of the onic acids. For this purpose, halogens and hypohalites are used (see Chapter 4). [Pg.63]

Haloform reactions are generally performed with halogens in the presence of hydroxide [251] or directly with hypohalites [252]. Alternative methods affording carboxylic acids from methyl ketones (or other enolizable substrates) include the aerobic oxidation in the presence of a catalytic amount of dinitrobenzene [253] with a base in a dipolar aprotic solvent such as DMF [254] or HMPT (hexamethylphospho-ric triamide) [255, 256] and the use of stoichiometric quantities of hypervalent iodide derivatives [95, 257] or nitrosylpentacyanoferrate [258]. Furthermore, metal catalysts can be used, and systems such as tert-butyl hydroperoxide in the presence of rhenium oxide [259], oxygen in combination with a copper complex [260], heteropolyacids [261] and Mn"/Co" systems [262] were found to be applicable. Finally, aryl ketones are selectively oxidized to aliphatic carboxylic acids by treatment with periodate [81] in the presence of ruthenium trichloride [263]. [Pg.217]


See other pages where Hypohalites metal is mentioned: [Pg.149]    [Pg.241]    [Pg.222]    [Pg.10]    [Pg.284]    [Pg.2433]    [Pg.93]    [Pg.702]    [Pg.1926]    [Pg.160]    [Pg.485]    [Pg.2345]    [Pg.83]    [Pg.93]    [Pg.66]    [Pg.161]    [Pg.130]    [Pg.268]    [Pg.197]    [Pg.540]    [Pg.642]    [Pg.286]    [Pg.149]    [Pg.379]   


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Hypohalite

Hypohalites

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