Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

1,2-Diperoxides

Acetylhydroperoxides, cyclic 1,1-Diperoxides Monoperoxycarbonic acid esters... [Pg.598]

Hydroxyall l Hydroperoxyall l Peroxides. There is evidence that hydroxyalkyl hydroperoxyalkyl peroxides (2, X = OH, Y = OOH) exist in equihbrium with their corresponding carbonyl compounds and other a-oxygen-substituted peroxides. For example, reaction with acyl haUdes yields diperoxyesters. Dilute acid hydrolysis yields the corresponding ketone (44). Reduction with phosphines yields di(hydroxyalkyl) peroxides and dehydration results in formation of cycHc diperoxides (4). [Pg.116]

Thermal decomposition of hydroxyalkyl hydroperoxyalkyl peroxides produces mixtures of starting carbonyl compounds, mono- and dicarboxyHc acids, cycHc diperoxides, carbon dioxide, and water. One specific hydroxyalkyl hydroperoxyalkyl peroxide from cyclohexanone (2, X = OH, Y = OOH) is a soHd that is produced commercially as a free-radical initiator and bleaching agent (see Table 5). On controlled decomposition, it forms 1,12-dodecanedioic acid (150). [Pg.116]

R = cyl), eg, with -nitrobenzoyl chloride. Upon reaction with lead tetraacetate, di(hydroperoxyalkyl) peroxides can also be converted to cycHc diperoxides (4). They are also converted to symmetrical or unsymmetrical cycHc triperoxides (5) in the presence of a second ketone and a catalyst, eg, CuSO -HCl (44,119). [Pg.116]

Cyclic Peroxides. CycHc diperoxides (4) and triperoxides (5) are soHds and the low molecular weight compounds are shock-sensitive and explosive (151). The melting points of some characteristic compounds of this type are given in Table 5. They can be reduced to carbonyl compounds and alcohols with zinc and alkaH, zinc and acetic acid, aluminum amalgam, Grignard reagents, and warm acidified iodides (44,122). They are more difficult to analyze by titration with acidified iodides than the acycHc peroxides and have been sucessfuUy analyzed by gas chromatography (112). [Pg.116]

Acid hydrolysis of peroxides (4) and (5) generates carbonyl compounds (parent ketones or aldehydes) and hydrogen peroxide. Basic hydrolysis of cycHc diperoxides with a-hydrogen (those from aldehydes) yields carboxyHc acids (44) ... [Pg.116]

Most ozonolysis reaction products are postulated to form by the reaction of the 1,3-zwitterion with the extmded carbonyl compound in a 1,3-dipolar cycloaddition reaction to produce stable 1,2,4-trioxanes (ozonides) (17) as shown with itself (dimerization) to form cycHc diperoxides (4) or with protic solvents, such as alcohols, carboxyUc acids, etc, to form a-substituted alkyl hydroperoxides. The latter can form other peroxidic products, depending on reactants, reaction conditions, and solvent. [Pg.117]

By-products include ozonides (17). Other peroxidic products including polymeric peroxides and polymeric ozonides can form, depending on reaction conditions, solvent, and olefin used. A variety of cycHc diperoxides (4) have been obtained by ozonolysis of olefins. Both cis- and... [Pg.117]

Another butadiene oxidation process to produce butanediol is based on the 1,4-addition of /-butyl hydroperoxide to butadiene (108). Cobalt on siHca catalyzes the first step. This is followed by hydrogenation of the resulting olefinic diperoxide to produce butanediol and /-butyl alcohol. [Pg.343]

When hydrogen peroxide is added to an acid solution of Cr(VI), a deep blue color, iadicating the formation of chromium (VI) oxide diperoxide [35262-77-2] is observed. This compound is metastable and rapidly decomposes to Cr(III) and oxygen at room temperature. The reaction... [Pg.137]

In order to induce the free-radical chain reaction, a starter compound such as dibenzoyl diperoxide, azo-Zj -(isobutyronitrile) or tcrt-butyl hydroperoxide or UV-light is used. The commercially available, technical grade N-bromosuccinimide contains traces of bromine, and therefore is of slight red-brown color. Since a small amount of elemental bromine is necessary for the radical... [Pg.300]

Experimental evidence is available to show that at room temperature diperoxides are formed in polyethylene, whereas polypropylene and polyvinyl chloride generate hydroperoxides. The temperature at which the peroxides decompose and initiate grafting depends on the type of polymer used. [Pg.509]

Pimelic Acid (Heptanedioic Acid or 1,5-Pentane-dicarboxytlc Acid). HOOC.(CH2)s.COOH mw 160.17 white prisms mp 106° bp 272° at 100mm (subl), and 212° at 10mm d 1.329 g/cc at 15°. Sol in w, ethanol, eth and hot benz. Prepn is by oxidn of cycloheptanone, capric acid or oleic acid treatment of salicylic acid with Na in amyl ale, or by decarboxylating 1,1,5,5-pentanetetracarboxylic acid with heat Pimelic acid has been combined with cis and trans-, 4-cyclohexanediol to give polyesters, and with m-xylene-ce,ol -diamine or poly-methylenediamines to form polyamides. With diperoxides, the acid forms resins. It is also used as the parent compd to form the expls presented below... [Pg.778]

In PE, these trapped radicals have been identihed as, mainly, alkyl and allyl radicals with the stmctures (—CH2CHCH2—) and (—CH—CH=CH—) [134,135]. In the presence of oxygen, the polymeric radicals will react to form diperoxides and hydroperoxides, as well as certain amount of less stable peroxy radicals (—CH2OO ). [Pg.869]

Tetraazido benzene quinone Tetraethylammonium perchlorate (dry) Tetramethylene diperoxide dicarbamide Tetranitro diglycerin... [Pg.330]

The assessors experienced an explosion while drying the oxide in ethyl ether. Rather drastic precautions are recommended in handling it [1], A preparation, allowed to stand for a week rather than the day specified, exploded during concentration [2], Amine oxides from the standard preparation are inclined to retain hydrogen peroxide of hydration unless it is destroyed during work-up. The perox-idate (or diperoxidate) of dimethylamine oxide would be expected to be far more dangerous than the oxide itself [3],... [Pg.463]

Interaction of alkenes with ozonised oxygen tends to give several types of products or their polymers, some of which show more pronounced explosive tendencies than others [1]. The cyclic ge/n-diperoxides are more explosive than the true ozonides [2], It has been calculated that ozonisation of the endothermic /rara-stilbene (AH°f +135.4 kJ/mol, 0.78 kJ/g) would give, in the event of decomposition of the unstable ozonide, an exothermic release of 1.41 kJ/g which would attain an adiabatic decomposition temperature approaching 750°C with a 27-fold pressure increase in a closed vessel [3],... [Pg.1867]

When dibenzal diperoxide 3 was added, at 200°, to a solution of di-benzanthrone a red chemiluminescence was observed67) this is also seen in the reaction of violanthrone (dibenzanthrone) with alkaline hydrogen peroxide/chlorine. [Pg.81]

Similar results were obtained with the diperoxides 5 (R phenyl) and 5 a (R />-chlorophenyl) and dibenzanthrone or other fluorescers (perylene, rhodamine B, 9.10-diphenylanthracene, anthracene, fluorescein), with quantum yields of the respective chemiluminescence in the range 3.29 X 10 8.... 5.26 X 10 6. [Pg.82]

Cyclic compounds, unnatural, 24 59 Cyclic cooligomerization, 16 238 Cyclic corrosion tests, 16 218 Cyclic diacyl peroxides, 18 473, 477 Cyclic dimethylsiloxanes, 22 575 Cyclic diperoxides, 18 461 Cyclic diperoxyketals, 18 457 Cyclic disulfides, antimicrobial properties of, 23 713... [Pg.241]

Dipentaerythritol, 2 46, 47 economic aspects, 2 52 manufacture, 2 51—52 physical properties of, 2 48t Dipentene, 24 491—492 uses for, 24 492 Diperoxides, cyclic, 18 459 Diperoxyacetals, 18 456 Diperoxycarboxylic acids, 18 464 Diperoxydodecanedioic acid, 4 62 Diperoxyketals, 14 281 18 456 boiling points of, 18 457t as free-radical initiators, 14 287-288 Diphasic solids, connectivity patterns for, 11 101... [Pg.276]

Two forms of acetone peroxides are known to exist a dimer called diacetone diperoxide (DADP) and a trimer called triacetone triperoxide (TATP). Figure 3.4 displays the chemical structures of each. [Pg.55]

Recently, the enthalpies of combustion and sublimation were measured for formaldehyde diperoxide, i.e. 1,2,4,5-tetroxane , from which the enthalpies of formation could be derived. These results were shown to be in good agreement with quantum chemical... [Pg.164]


See other pages where 1,2-Diperoxides is mentioned: [Pg.341]    [Pg.525]    [Pg.63]    [Pg.286]    [Pg.305]    [Pg.52]    [Pg.552]    [Pg.322]    [Pg.278]    [Pg.589]    [Pg.52]    [Pg.211]    [Pg.211]    [Pg.111]    [Pg.114]    [Pg.136]    [Pg.476]    [Pg.509]    [Pg.509]    [Pg.509]    [Pg.750]    [Pg.678]    [Pg.687]    [Pg.476]    [Pg.261]    [Pg.337]    [Pg.64]    [Pg.81]    [Pg.81]    [Pg.82]    [Pg.82]    [Pg.184]    [Pg.74]    [Pg.331]    [Pg.156]    [Pg.164]    [Pg.545]    [Pg.708]    [Pg.256]   


SEARCH



Cross diperoxides, formation

Cyclic diperoxides

Diacetone Diperoxide

Diacetone Diperoxide Peroxides

Diacetone diperoxide, explosive

Diacetophenone Diperoxide

Dibenzal diperoxide

Diethyl ketone diperoxide

Hydroperoxides 1,1-diperoxides

Methyl ethyl ketone diperoxide

Peroxides diperoxides

Tetramethylene diperoxide dicarbamide

Tetraoxymethylene diperoxide

© 2024 chempedia.info