From hydroperoxides

A process variation of the extraction of 2-isopropylnaphthalene hydroperoxide from the cmde oxidation product with an alkylene glycol has been patented (71). The 2-naphthalenol plant of American Cyanamid, which was using the hydroperoxidation process and had a 14 x 10 t /yr capacity (72), ceased production in 1982, leaving the United States without a domestic producer of 2-naphthol. The 2-naphthol capacity in the Western world is approximately 50 x 10 t/yr, with ACNA, Italy and Hoechst AG, Germany operating the largest plants. China produces about 7 x 10 t/yr. Other important producing countries are Poland, Romania, the former Czechoslovakia, and India (35,52). 

In the preparation of hydroperoxides from hydrogen peroxide, dialkyl peroxides usually form as by-products from the alkylation of the hydroperoxide in the reaction mixture. The reactivity of the substrate (olefin or RX) with hydrogen peroxide is the principal restriction in the process. If elevated temperatures or strongly acidic or strongly basic conditions are required, extensive decomposition of the hydrogen peroxide and the hydroperoxide can occur. 

Saponification of alkyl peroxyesters yields alkyl hydroperoxides and carboxylic acids or their alkali metal salts. a-Ether-substituted peroxides can be hydrolyzed to the unsubstituted alkyl hydroperoxides, eg, tert-huty hydroperoxide from tert-huty 2-oxacyclohexyl peroxide [28627-46-5] (62) ... 

Hydroxyalkyl hydroperoxides from cycHc ketones (1), where X = OH, R =, H and R, R = alkylene, apparentiy exist in solution as equihbrium mixtures of the cycHc ketone, hydrogen peroxide, and other peroxides, eg, the dihydroperoxide (1) in which X = OOH, and dialkyl peroxides (2) where X = OH and Y = OH or OOH. Due to the existence of this equihbrium, the latter two dialkyl peroxides react as mixtures of monomeric hydroperoxides in solution. 

As with other hydroperoxides, hydroxyaLkyl hydroperoxides are decomposed by transition-metal ions in an electron-transfer process. This is tme even for those hydroxyaLkyl hydroperoxides that only exist in equiUbrium. For example, those hydroperoxides from cycHc ketones (R, R = alkylene) form an oxygen-centered radical initially which then undergoes ring-opening -scission forming an intermediate carboxyalkyl radical (124) ... 

Alkoxyall l Hydroperoxides. These compounds (1, X = OR , R = H) have been prepared by the ozonization of certain unsaturated compounds in alcohol solvents (10,125,126). 2-Methoxy-2-hydroperoxypropane [10027-74 ] (1, X = OR , R" = methyl), has been generated in methanol solution and spectral data obtained (127). A rapid exothermic decomposition upon concentration of this peroxide in a methylene chloride—methanol solution at 0°C has been reported (128). 2-Bromo-l-methoxy-l-methylethylhydroperoxide [98821-14-8]has been distilled (bp 60°C (bath temp.), 0.013 kPa) (129). Two cycHc alkoxyaLkyl hydroperoxides from cyclodecanone have been reported (1, where X = OR R, R = 5-oxo-l, 9-nonanediyl) with mp 94—95°C (R" = methyl) and mp 66—68°C (R" = ethyl) (130). Like other hydroperoxides, alkoxyaLkyl hydroperoxides can be acylated or alkylated (130,131). 

Chemical Properties. Alkyl peroxyesters are hydroly2ed more readily than the analogous nonperoxidic esters and yield the original acids and hydroperoxides from which they were prepared rather than alcohols and peroxyacids ... 

Haemoglobin-derived haem iron has multiple pro-inflammatory effects resulting from its ability to initiate decomposition of lipid hydroperoxides from PUFAs. In... 

Autoxidation may in some cases be of preparative use thus reference has already been made to the large-scale production of phenol+ acetone by the acid-catalysed rearrangement of the hydroperoxide from 2-phenylpropane (cumene, p. 128). Another example involves the hydroperoxide (94) obtained by the air oxidation at 70° of tetrahydro-naphthalene (tetralin) the action of base then yields the ketone (a-tetralone, 95), and reductive fission of the 0—0 linkage the alcohol (a-tetralol, 96) ... 

Secondly, the interaction of hindered amines with hydroperoxides was examined. At room temperature, using different monofunctional model hydroperoxides, a direct hydroperoxide decomposition by TMP derivatives was not seen. On the other hand, a marked inhibitory effect of certain hindered amines on the formation of hydroperoxides in the induced photooxidation of hydrocarbons was observed. Additional spectroscopic and analytical evidence is given for complex formation between TMP derivatives and tert.-butyl hydroperoxide. From these results, a possible mechanism for the reaction between hindered amines and the oxidizing species was proposed. 

Stabilizing additives for polymers usually scavenge free radicals or hydroperoxides from the system. The effect of such additives is depicted in reactions... 

Table 3 The rate constants k determined from chemiluminescence experiments of Figure 15 and Equation (14) and the rate constants k of decomposition of hydroperoxides from literature... 

If we presume that oxidation of polymer PH takes place according to the Scheme 2 of Bolland-Gee mechanism, in which reactions 2, 3, 5, 6, 7, 8, 9 and 10 predominate, involving initiation, propagation and termination of the free radical process. The production of primary radicals by the reaction 1 is governed rapidly by decomposition of hydroperoxides. From the shape of kinetic runs it may be assumed that decomposition of hydroperoxides has the character of a bimole-cular reaction (reaction 5) even in a very short time after the start of experiment. 

Dimethylbenzofurazan 255 was transformed by 02 produced by irradiation of C60 into 4,7-dimethylbenzofur-azan 4,7-endoperoxide 256 in CDCI3 or CD2CI2 at 0°C in excellent yields. The endoperoxide 256 decomposed back to compound 255 at room temperature. When tetramethylethylene (TME) was added to the decomposing endoperoxide 256 at 37 °C, the hydroperoxide from reaction of TME with 02 was detected (Scheme 67) <2001TL987>. 

Calculation of O—H Bond Dissociation Energies in Ether Hydroperoxides from Kinetic Data (See Table 2.8 and Table 7.16)... 

Blatter, F., Sun, H. and Frei, H. (1996). Highly selective formation of tert-butyl hydroperoxide from the reaction of isobutane and 02 in a zeolite under visible light. Chem. Eur. J. 2, 385-389... 

Cyclic enone, 12 185 Cyclic ethers, 10 567, 569 12 663 polymerization, 14 271 Cyclic fatigue, in ceramics, 5 633-634 Cyclic gas generators, 6 786-787, 789, 827 Cyclic halides, 19 56 Cyclic hexakis(thio-l,4-phenylene), melt polymerization of, 23 705 Cyclic hydrocarbons, 13 687 Cyclic hydroxyalkyl alkyl peroxide, 18 454 Cyclic ion exchange operation, 14 408-413 Cyclic ketones, 12 176, 177 14 590-592. See also Cyclic 1,2-diketones physical properties of, 14 591t hydroxyalkyl hydroperoxides from, 18 450... 

Frimer, A. A., J. Org. Chem., 1977, 42, 3194-3196, footnote 7 A new method of preparation involves interaction of ally lie halides in solvents with 98% hydrogen peroxide in presence of silver ion and base at ambient temperature under argon. The reactions must be run in the dark to prevent precipitation of metallic silver, which will catalyse decomposition of the hydroperoxide or excess hydrogen peroxide. In an experiment not run in the dark, the hydroperoxide from 3-chlorocyclohexene ignited spontaneously after isolation and concentration. 

The value is from the liquid phase enthalpy of reaction between cyclohexanone and tert-butyl hydroperoxide from V. L. Antonovskii, E. V. Federova, N. E. Shrivel and V. D. Emelin, Kinet. Ratal., 30, 1235 (1989). 

SCHEME 7. Synthesis of hydroperoxides from electrochemically generated superoxide and alkyl halides... 

SCHEME 12. Synthesis of hydroperoxides from silyl enol ethers TABLE 3. Preparation of alkyl hydroperoxides via singlet oxygen oxygenation... 

SCHEME 15. Preparation of hydroperoxides from peroxide precursors... 

SCHEME 16. Preparation of alkyl hydroperoxides from alkyl bromides... 

The quenching mechanism of Vitamin E (21) toward hydroperoxides is depicted in equation 11 (Section II.A.2.d). The structure of products 38 obtained when quenching hydroperoxides from phosphatidylcholines (155) was elucidated by the usual MS and NMR techniques. ... 

Such a rearrangement was detected only in the presence of sulfuric acid, and furthermore at 100°C. it was supplanted by a homolytic breakdown. The products found in the purely thermal decomposition—methyl vinyl ketone and methyl vinyl carbinol—are in fact consistent with the behavior of alkyl hydroperoxides and are analogous to the products produced from the cyclic allylic hydroperoxide from cyclohexene (2). 

C. J. Norton Have you any indication of geometric isomers in the hydroperoxides from 2-butene Would you expect differences in stabilities ... 

The hydroperoxide from the more acidic fluorene prefers to react via the decomposition process (Reaction 6 or 7) rather than the reductive reaction with dimethyl sulfoxide (Reaction 3). 

We were unable to detect any signal which could be assigned to an alkoxy radical in the titanous ion reduction (17, 38) of ferf-butyl hydroperoxide from +25° to — 60°C., nor could an alkoxy radical signal be... 

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