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Allyl alcohols peroxides

Allyl alcohol [107-18-6] M 58.1, b 98°, d4 0,857, no 1.4134. Can be dried with K2CO3 or CaSOa, or by azeotropic distn with benzene followed by distn under nitrogen. It is difficult to obtain peroxide free. Also reflux with magnesium and fractionally distd [Hands and Norman Ind Chem 21 307 1945],... [Pg.100]

Nickel peroxide is a solid, insoluble oxidant prepared by reaction of nickel (II) salts with hypochlorite or ozone in aqueous alkaline solution. This reagent when used in nonpolar medium is similar to, but more reactive than, activated manganese dioxide in selectively oxidizing allylic or acetylenic alcohols. It also reacts rapidly with amines, phenols, hydrazones and sulfides so that selective oxidation of allylic alcohols in the presence of these functionalities may not be possible. In basic media the oxidizing power of nickel peroxide is increased and saturated primary alcohols can be oxidized directly to carboxylic acids. In the presence of ammonia at —20°, primary allylic alcohols give amides while at elevated temperatures nitriles are formed. At elevated temperatures efficient cleavage of a-glycols, a-ketols... [Pg.248]

The mechanism for such a process was explained in terms of a structure as depicted in Figure 6.5. The allylic alcohol and the alkyl hydroperoxide are incorporated into the vanadium coordination sphere and the oxygen transfer from the peroxide to the olefin takes place in an intramolecular fashion (as described above for titanium tartrate catalyst) [30, 32]. [Pg.193]

Lewis acids such as SnCl4 also catalyze the reaction, in which case the species that adds to the alkenes is H2C —O— SnC. Montmorillonite KIO clay containing zinc(IV) has been used to promote the reaction. The reaction can also be catalyzed by peroxides, in which case the mechanism is probably a free-radical one. Other transition metal complexes can be used to form allylic alcohols. A typical example is. ... [Pg.1242]

Heteropoly acids can be synergistically combined with phase-transfer catalysis in the so-called Ishii-Venturello chemistry for oxidation reactions such as oxidation of alcohols, allyl alcohols, alkenes, alkynes, P-unsaturated acids, vic-diols, phenol, and amines with hydrogen peroxide (Mizuno et al., 1994). Recent examples include the epoxidations of alkyl undecylenates (Yadav and Satoskar, 1997) and. styrene (Yadav and Pujari, 2000). [Pg.138]

Hexafluoroacetone and hydrogen peroxide in buffered aqueous solution can epoxidize alkenes and allylic alcohols.101 N, Af-Dialkylpiperidin-4-one salts are also good catalysts for epoxidation.102 The polar effect of the quaternary nitrogen enhances the... [Pg.1100]

Syn-hydroxylation of alkenes is also effected by a catalytic amount of osmium tetroxide in the presence of hydrogen peroxide. Originally developed by Milas, the reaction can be performed with aqueous hydrogen peroxide in solvents such as acetone or diethyl ether.58 Allyl alcohol is quantitatively hydroxylated in water (Eq. 3.12).59... [Pg.55]

Ti compounds also promote epoxidation of olefins, mainly allyl alcohol moieties in the presence of peroxides (Scheme 32).1 5... [Pg.412]

Usually the allylic peroxides are not the final products but they are reduced to allylic alcohols as in the synthesis of E-5-cyclodecenone (6.14)620). [Pg.75]

As a further example of a hydroxyl-assisted epoxidation, geraniol and nerol bearing two isolated C=C double bonds were regioselectively epoxidized with TS-1 at the 2-position (near the OH group), as reported by Kumar et al. (795). On the basis of these results, Kumar et al. (195) proposed that the transition state of the epoxidation of allylic alcohols involves coordination of the alcoholic functional group to the Ti active site and that the double bond interacts with one of the peroxidic oxygen atoms, not with the titanium site (Scheme 9). [Pg.96]

The highly chemo-, regio-, and diastereoselective and stereospecific epoxidation of various allylic alcohols with only 1 equivalent of hydrogen peroxide in water solvent could be efficiently catalyzed by an isolated dinuclear peroxotungstate [W203(02)4(H20)2]2 [93,94] ... [Pg.474]

There are several other routes to acetone of minor importance air oxidation of IPA reaction between IPAand acrolein for the production of allyl alcohol, with acetone as the by-product vapor phase oxidation of butane coproduction when IPA is oxidized yielding acetone and H2O2, hydrogen peroxide, the principal ingredient of bleach and by-product production from the manufacture of methyl ethyl ketone. [Pg.243]

Photolytic. Distilled water irradiated with UV light (X = 290 nm) yielded the following photolysis products 2-chloro-l-propanol, allyl chloride, allyl alcohol, and acetone. The photolysis half-life in distilled water is 50 min, but in distilled water containing hydrogen peroxide, the half-life decreased to <30 min (Milano et al, 1988). [Pg.433]

Enantioselective epoxidation of allylic alcohols using t-butyl peroxide, titanium tetra-wo-propoxide, and optically pure diethyl tartrate. [Pg.533]

Allylic acetates are usually prepared by esterification from allylic alcohols. However, the corresponding alcohols are often only accessible by the fairly expensive hydride reduction of carbonyl compounds. Consequently, direct allylic functionalization of easily available olefins has been intensively investigated. Most of these reactions involve peroxides or a variety of metal salts.However, serious drawbacks of these reactions, (e.g. toxicity of some metals, stoichiometric reaction conditions, or nongenerality) may be responsible for their infrequent use for the construction of allylic alcohols or acetates. [Pg.184]

Dogterom P, Nagelkerke JF, van Steveninick J, et al. 1988. Inhibition of lipid peroxidation by disulfiram and diethydithiocarbamate does not prevent hepatotoxin-induced cell death in isolated rat hepatocytes. A study with allyl alcohol, tert-butyl hydroperoxide, diethyl maleate, bromoisovalerylurea and carbon tetrachloride. Chem Biol Interact 66 251-265. [Pg.158]


See other pages where Allyl alcohols peroxides is mentioned: [Pg.1924]    [Pg.1924]    [Pg.347]    [Pg.333]    [Pg.51]    [Pg.766]    [Pg.225]    [Pg.182]    [Pg.478]    [Pg.189]    [Pg.241]    [Pg.1084]    [Pg.1085]    [Pg.1338]    [Pg.53]    [Pg.21]    [Pg.460]    [Pg.243]    [Pg.937]    [Pg.72]    [Pg.197]    [Pg.115]    [Pg.236]    [Pg.436]    [Pg.33]    [Pg.743]    [Pg.92]    [Pg.362]    [Pg.385]    [Pg.410]   
See also in sourсe #XX -- [ Pg.33 ]




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Allyl peroxides

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