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Oxidation of glycols

In all circumstances it is important to ensure that the inhibitor is chemically compatible with the liquid to which it is added. Chromates, for example, cannot be used in glycol antifreeze solutions since oxidation of glycol by chromate will reduce this to the trivalent state which has no inhibitive properties. [Pg.782]

The name Etard reaction is often applied to any oxidation with chromyl chloride, for example, oxidation of glycols (19-7) and Alkenes (19-10). [Pg.1584]

Urzua U, PJ Kersten, R Vicuna (1998) Manganese peroxidase-dependent oxidation of glycolic and oxalic acids synthesized by Ceriporiopsis subvermispora produces extracellular hydrogen peroxide. Appl Environ Microbiol 64 68-73. [Pg.146]

DuPont has developed a process for the manufacture of glyoxylic acid by aerobic oxidation of glycolic acid (Fig. 2.33) mediated by whole cells of a recombinant methylotrophic yeast (Gavagnan et al, 1995). The glycolic acid raw material is readily available from the acid-catalysed carbonylation of formaldehyde. Traditionally, glyoxylic acid was produced by nitric acid oxidation of acetaldehyde or glyoxal, processes with high E factors, and more recently by ozonolysis of maleic anhydride. [Pg.50]

Lead tetraacetate is used as a highly selective oxidizing agent in organic synthesis. This includes oxidation of glycols into aldehydes, preparation of cyclohexyl acetate, production of oxahc acid, and in structural analysis of sugars. [Pg.479]

Similar mechanisms were postulated for the oxidation of glycols by periodate (32) and Ce(IV) (33, 34), and for the oxidation of glycerol by Ce(IV) (44). In these cases the existence of intermediate complexes was demonstrated. The oxidation of formaldehyde by Ce(IV) was also claimed to involve a pre-equilibrium of a Ce(IV)-formaldehyde complex (51). A similar complex was postulated in the formalde-hyde-Mn04 reaction (49, 87). The oxidation of isopropyl alcohol by chromate ions follows a similar mechanism, and a chromate ester was formed as intermediate (94). [Pg.128]

In Ref 2 is given the following general equation of oxidation of glycols (compounds with adjacent hydroxyl groups) by periodic acid ... [Pg.124]

Another is the oxidation of a secondary alcohol to a ketone (9-3), where A and B are alkyl or aryl groups and Z is also CrOjH. In the lead tetraacetate oxidation of glycols (9-7) the mechanism also follows this pattern, but the positive leaving group is carbon instead of hydrogen. It should be noted that the cleavage shown is an example of an E2 elimination. [Pg.1161]

Catalysis of the oxidation of allyl and crotyl alcohols with chloramine-T, 375 chloramine-B, bromamine-T, and bromamine-B Catalysis of the chloramine-T oxidation of glycolic and lactic acids 376... [Pg.280]

Oxidation of glycol esters to ene-S-lactones. Reaction of glycal esters with m-chloroperbenzoic acid involves the expected epoxidation followed by cleavage of the oxide by the /n-chlorobenzoic acid formed. However, in the presence of BF3, the reaction produces a,/ -unsaturated 5-lactones, usually in excellent yield. This oxidation is also possible with pyridinium chlorochromate and BF3 as catalyst, but in lower yield.1... [Pg.378]

It was also shown that the ratio of oxidized alcohol to oxidized Fe2+ could be greater then one. Baxendale and Wilson (1957) showed that hydroxyl radical initiating the chain polymerization of olefins by hydrogen peroxide was the same process as the rapid oxidation of glycolic acid. Merz and Waters (1947) confirmed that simple water-soluble alcohols are oxidized rapidly by Fenton s reagent. The primary alcohols are oxidized to aldehydes, which are further oxidized at comparable rates by exactly the same mechanism. Merz and Waters proposed a mechanism of chain oxidation of alcohols and aldehydes by sodium persulfate, hydrogen peroxide, and an excess of ferrous salt as follows ... [Pg.185]

The Editors note with regret the recent passing of Louis Malaprade, University of Nancy, discoverer of the stoichiometric oxidation of glycols by periodate, a reaction that has had such profound implications in the structural investigation of carbohydrates and of Karl Freudenberg, Heidelberg, last surviving student of Emil Fischer s, pioneer of important stereochemical concepts, and a scientist whose extensive contributions to synthesis included the classic, widely used acetone derivatives (isopropylidene acetals) of the monosaccharides. [Pg.420]

DuPont has developed a process for the manufacture of glyoxylic acid, a large volume fine chemical, by aerobic oxidation of glycolic acid, mediated by resting... [Pg.31]

The anodic oxidation method is highly efficient for the oxidative cleavage of glycols (22) and related compounds. The oxidation of glycols and glycol ethers in methanol results in a clean cleavage to the corresponding carbonyl compounds (equation 44). ... [Pg.803]

The initiation step of this anodic oxidation of glycols may be the electron transfer from the lone pah-electrons of the oxygen atom to the anode. This anodic cleavage of 1,2-glycols has beat utilized for a variety of organic syntheses. ... [Pg.803]


See other pages where Oxidation of glycols is mentioned: [Pg.231]    [Pg.378]    [Pg.1509]    [Pg.320]    [Pg.389]    [Pg.650]    [Pg.130]    [Pg.142]    [Pg.757]    [Pg.119]    [Pg.254]    [Pg.1321]    [Pg.95]    [Pg.132]    [Pg.378]    [Pg.134]    [Pg.182]    [Pg.182]    [Pg.112]    [Pg.109]    [Pg.331]    [Pg.757]    [Pg.705]    [Pg.803]    [Pg.705]    [Pg.803]   
See also in sourсe #XX -- [ Pg.538 ]

See also in sourсe #XX -- [ Pg.538 ]

See also in sourсe #XX -- [ Pg.377 , Pg.378 ]




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Glycolic Oxidation

Glycols, oxidation

Hydration of alkene oxides to glycols

Oxidative cleavage of glycols and related compounds

Periodate Oxidation of Glycols and Carbohydrates

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