Oxidation alcohol to carbonyl

The anion in KRu04 has a slightly flattened tetrahedral structure (Ru-O 1.73 A). Organic-soluble salts like Pr4NRu04 are selective mild oxidants that will oxidize alcohols to carbonyl compounds but will not affect double bonds [54a]. ESR indicates that Ru04 (g = 1.93 gy = 1.98 gz = 2.06) has a compressed tetrahedral geometry with the electron in dz2 [54b]. 

The electrochemically generated Cr =0 complexes are able to oxidize alcohols to carbonyl compounds according to the following catalytic cycle, sketched in Sch. 12. 

Molybdenum-peroxo compounds have been shown to achieve a variety of selective oxidations they a-hydroxylate enolizable ketones, presumably via epoxidation of the enolate (equation 27) 163 they cause Baeyer-Villiger lactonization of cyclic ketones, probably via the formation of five-membered trioxametallacycles (equation 28) 164 they oxidize alcohols to carbonyl compounds... 

Potassium ferrate, K2Fe04, is isomorphous with chromates and readily oxidizes alcohols to carbonyl compounds in the presence of alkali.286,287 The purple color of ferrate ion fades with the progress of the reaction. Yields as high as 96% have been reported for the oxidation of cinnamyl alcohol to cinnamaldehyde (equation 111).287... 

Oxidation. In the presence of Cl2Ru[P(C6H5)3]3, iodosylbenzene oxidizes alcohols to carbonyl compounds.1 The oxidation is similar to oxidation with N-methylmorpholine, which is also catalyzed by Ru(II) (7, 244). Thus oxidation of primary alcohols can proceed to carboxylic acids, but stops at the aldehyde if... 

Sodium metiq>eriodate, NaI04, is a two-electron chemoselective oxidant and when absorbed on alumina oxidizes alcohols to carbonyl compounds and sulfides to sulfoxides without overoxidation to sul-fones. 2 Alkenic double bonds in the substrate remain intact during this oxidation. Typically reactions are performed in 95% ethanol at room temperature for a few hours and with good (85-90%) yields. 

NAD% the oxidized form of NADH, is a biological oxidizing agent capable of oxidizing alcohols to carbonyl compounds (it forms NADH in the process). NAD is synthesized from the vitamin niacin, which can be obtained from soybeans among other dietary sources. Breakfast cereals are fortified with niacin to help people consume their recommended daily allowance of this B vitamin. 

Nickel peroxide, prepared by adding an alkaline solution of 6% sodium hypochlorite to a solution of nickel sulfate hydrate at 20 °C, is used to oxidize alcohols to carbonyl compounds or carboxylic acids. The oxidation... 

The mechanism of the Ley oxidation is complex and the exact nature of the species involved in the catalytic cycle is unknown. The difficulty in establishing an exact mechanism arises from the fact that the complexes of Ru ", Ru ", Ru , Ru and Ru are all capable of stoichiometrically oxidizing alcohols to carbonyl compounds. The TRAP reagent can oxidize alcohols stoichiometrically as a three-electron oxidant and can also be used as a catalyst when a co-oxidant is present (e.g., NMO, TMAO, or hydroperoxides). Data suggests that the oxidation proceeds via the formation of a complex between the alcohol and TRAP (ruthenate ester). It was also found that the stoichiometric oxidation of isopropyl alcohol with TRAP is autocatalytic and the catalyst is suspected to be colloidal RUO2. Small amounts of water decrease the degree of autocatalysis. This observation is supported by the finding that the addition of molecular sieves improves the efficiency of the reaction. 

Allylic oxidation. This novel oxidizing agent is prepared from C6p6 and NaSeH followed by exposing the product to O2, O3, and H2O in sequence. It converts alkenes to enones, besides oxidizing alcohols to carbonyl compounds. 

Oxidation of alcohols. This triazoline-3,5-dione has been used to oxidize alcohols to carbonyl compounds with formation of 4-phenyl-I,2,4-triazolidine-3,5-dione. ... 

Catalytic oxidation of alcohols by cis-dioxomolybdenum(VI) complexes, involving oxygen atom transfer from sulfoxides has been reported [1397]. Catalytic amounts of cis-dioxomolybdenum(Vl) complexes in association with sulfoxides can be used to oxidize alcohols to carbonyl compounds. For primary alcohols, the oxidation to the aldehyde is selective, and no further oxidation to the carboxyUc add is observed. The oxidation is most effective for benzylic and allylic alcohols. The mechanism... 

A slightly different procedure for oxidizing alcohols to carbonyl compounds has been applied by Rivero and co-workers [1363]. When triphosgene was added to DMSO at —78 °C, no evolution of carbon dioxide was observed prior to addition of the alcohol, possibly suggesting the formation of a mixture of reactive intermediates 1887 and 1888. At room temperature, DMSO reacts exothermically with triphosgene with the evolution of carbon dioxide [1363]. 

The reaction can also be used to oxidize alcohols to carbonyl compounds. In this case, acetone is used as the acceptor, and the alcohol to be oxidized is used to form the aluminium oxide (Fig. 19.126). 

Section 19.14) A method of oxidizing alcohols to carbonyl compounds, or, equivalently, of reducing carbonyls to alcohols, that uses an aluminum atom to clamp the partners in the reaction together. A hydride shift is involved in the crucial step. 

Potassium ferrate, K2pe04, is a mild reagent for the oxidation of primary alcohols and primary alkylamines to aldehydes, and of secondary alcohols to ketones. lodonium nitrate, INO3, is reported to oxidize alcohols to carbonyl compounds electron-withdrawing groups adjacent to the alcohol carbon cause a marked decrease in reactivity olefinic alcohols undergo preferential electrophilic addition to the double bond. ... 

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