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Oxidation ketones from

Anodic oxidation Ketones from tert. alcohols... [Pg.349]

Copper-magnesium oxide Ketones from sec. alcohols in the vapor phase... [Pg.399]

Mercuric chloride]mercuric oxide Ketones from cyclic thioketals s. 18,663... [Pg.94]

Nitrogen dioxide-nitric oxide Ketones from oxazolidine N-oxyls... [Pg.76]

Chromium trioxidejacetic acid Benzylic oxidation Ketones from hydrocarbons s. 26, 165 with Cr03/H2S04, cyclic a-iminoketones, cf. W. F. Midine and N. F. Albertson, J. Med. Chem. 15, 1278 (1972)... [Pg.393]

Ethyl a-naphthylacetate is prepared as follows. To a solution of 10 g. of the diazo ketone in 150 ml. of ethanol at 55-60°, add a small amount of aslurry of silver oxide, prepared from 10 ml. of 10 per cent, aqueous silver nitrate and stirred with 25 ml. of ethanol. As soon as the evolution of nitrogen subsides, introduce more of the silver oxide and continue the process until all the slurry has been added. Reflux the mixture for 15 minutes, add 2-3 g. of decolourising carbon, filter and evaporate the alcohol on a water bath. Distil the residue and collect the ethyl a-naph-thylacetate at 176-178°/ 1 mm. the yield is 9 g. [Pg.905]

Methyl ketones are important intermediates for the synthesis of methyl alkyl carbinols, annulation reagents, and cyclic compounds. A common synthetic method for the preparation of methyl ketones is the alkylation of acetone derivatives, but the method suffers limitations such as low yields and lack of regioselectivity. Preparation of methyl ketones from olefins and acetylenes using mercury compounds is a better method. For example, hydration of terminal acetylenes using HgSO gives methyl ketones cleanly. Oxymercuration of 1-olefins and subsequent oxidation with chromic oxide is... [Pg.11]

Notable examples of general synthetic procedures in Volume 47 include the synthesis of aromatic aldehydes (from dichloro-methyl methyl ether), aliphatic aldehydes (from alkyl halides and trimethylamine oxide and by oxidation of alcohols using dimethyl sulfoxide, dicyclohexylcarbodiimide, and pyridinum trifluoro-acetate the latter method is particularly useful since the conditions are so mild), carbethoxycycloalkanones (from sodium hydride, diethyl carbonate, and the cycloalkanone), m-dialkylbenzenes (from the />-isomer by isomerization with hydrogen fluoride and boron trifluoride), and the deamination of amines (by conversion to the nitrosoamide and thermolysis to the ester). Other general methods are represented by the synthesis of 1 J-difluoroolefins (from sodium chlorodifluoroacetate, triphenyl phosphine, and an aldehyde or ketone), the nitration of aromatic rings (with ni-tronium tetrafluoroborate), the reductive methylation of aromatic nitro compounds (with formaldehyde and hydrogen), the synthesis of dialkyl ketones (from carboxylic acids and iron powder), and the preparation of 1-substituted cyclopropanols (from the condensation of a 1,3-dichloro-2-propanol derivative and ethyl-... [Pg.144]

Considerable interest arose during the 1970 s and 1980 s in the use of micro-organisms to produce useful fatty adds and related compounds from hydrocarbons derived from the petroleum industry. During this period, a large number of patents were granted in Europe, USA and Japan protecting processes leading to the production of alkanols, alkyl oxides, ketones, alkanoic adds, alkane dioic acids and surfactants from hydrocarbons. Many of these processes involved the use of bacteria and yeasts associated with hydrocarbon catabolism. [Pg.334]

This section lists examples of the replacement of hydrogen by ketonic groups, R-H R(C=0)-R . For the oxidation of methylenes, R2CH2 -> R2C=0, see section 170 (Ketones from Alkyls). [Pg.196]

For the oxidation of allylic alcohols to alkene ketones, see Section 168 (Ketones from Alcohols and Phenols)... [Pg.374]

For the oxidation of allylic methylene groups (C=C-CH2 C=C-C=0), see Section 170 (Ketones from Alkyls and Methylenes). [Pg.374]

Ruthenium tetroxide can also be used in the oxidation of alkenes. Conditions that are selective for formation of ketols have been developed.36 Use of 1 mol % of RuC13 and five equivalents of KHS05 (Oxone ) in an ethyl acetate-acetonitrile-water mixture gives mainly hydroxymethyl ketones from terminal alkenes. [Pg.1075]

A Catalytic Distillation Process for the One Step Synthesis of Methyl Isobutyl Ketone from Acetone Liquid Phase Kinetics of the Hydrogenation of Mesityl Oxide... [Pg.261]

Other mechanisms of ketone oxidation are also known and will be discussed in Chapter 8. Peracid, which is formed from aldehyde, oxidizes ketones with lactone formation (Bayer-Villiger reaction). [Pg.48]

Another factor complicating the situation in composition of peroxyl radicals propagating chain oxidation of alcohol is the production of carbonyl compounds due to alcohol oxidation. As a result of alcohol oxidation, ketones are formed from the secondary alcohol oxidation and aldehydes from the primary alcohols [8,9], Hydroperoxide radicals are added to carbonyl compounds with the formation of alkylhydroxyperoxyl radical. This addition is reversible. [Pg.295]

Oxidation of alcohol produces hydrogen peroxide and carbonyl compound simultaneously (aldehyde and ketone from primary and secondary alcohols, respectively). Carbonyl compound is formed as a result of alkylhydroxyperoxyl radical decomposition... [Pg.306]

The 1,3-dipolar addition to terminal alkenes of nitrile oxides, generated from nitromethylene derivatives of bicycloheptane, provides 9,ll-ethano-13,15-isoxazolinoprostanoids, PGH analogs, with alkyl, phenyl, or additional heterocyclic fragment in the oo-chain (461). Chemical transformations of 9,11-ethano-13,15-isoxazolinoprostanoids furnish prostanoids with bifunctional fragments of P-hydroxyketone and a-aminoalcohol in the oo-chain. The reaction of P-hydroxy ketones with methanesulfonyl chloride gives rise to prostanoids with an enone component in the oo-chain. 9,ll-Ethano-16-thiaprostanoids have been prepared, for the first time, by nucleophilic addition of thiols to the polarized double bond in the oo-chain. The 1,3-dipolar addition to terminal alkenes of nitrile oxides, generated from nitromethylene derivatives of bicycloheptane provides 9,ll-ethano-13,15-isoxazolinoprostanoids with an alkyl, phenyl, or additional heterocyclic fragment in the oo-chain (462). [Pg.91]

Bis(nitrile oxides) obtained from dialkylbenzenes have been claimed as low-temperature rubber vulcanization agents (517). Curing of poly(butadiene-co-acrylonitrile) with 2,4,6-trimethylisophthalodinitrile N-oxide produces rubbery material of good quality, however, curing of (polybutadiene) was unsuccessful (518). The solubility of dinitrile oxides and stability of their ketone solutions has been studied for their application as vulcanizing agents in the production of mbberized materials (519). [Pg.104]

The fragmentation is stereospecifically anti as shown by complementary geometry obtained in the cleavage of the epimeric pair of epoxycyclobutanones 91 and 92 (Eq. 110). The fragmentation product 93 of cyclobutanone 91 is transformable into the dimethyl ester of the pheromone of the Monarch butterfly. Considering the availability of the starting epoxy ketones from enones, the oxasecoalkylation serves to reorient the oxidation pattern with chain extension as summarized in Eq. 111. [Pg.62]

The intermolecular Heck reaction of halopyridines provides an alternative route to functionalized pyridines, circumventing the functional group compatibility problems encountered in other methods. 3-Bromopyridine has often been used as a substrate for the Heck reaction [124-126]. For example, ketone 155 was obtained from the Heck reaction of 3-bromo-2-methoxy-5-chloropyridine (153) with allylic alcohol 154 [125]. The mechanism for such a synthetically useful coupling warrants additional comments oxidative addition of 3-bromopyridine 153 to Pd(0) proceeds as usual to give the palladium intermediate 156. Subsequent insertion of allylic alcohol 154 to 156 gives intermediate 157. Reductive elimination of 157 gives enol 158, which then isomerizes to afford ketone 155 as the ultimate product This tactic is frequently used in the synthesis of ketones from allylic alcohols. [Pg.213]


See other pages where Oxidation ketones from is mentioned: [Pg.790]    [Pg.790]    [Pg.81]    [Pg.136]    [Pg.103]    [Pg.108]    [Pg.130]    [Pg.230]    [Pg.238]    [Pg.1284]    [Pg.1285]    [Pg.1528]    [Pg.170]    [Pg.398]    [Pg.182]    [Pg.241]    [Pg.222]    [Pg.468]    [Pg.408]   
See also in sourсe #XX -- [ Pg.240 ]




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Ketones oxidant

Ketones oxidation

Oxidative ketones

Oxidative ketonization

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