Oxidation hydroperoxides

An oxirane process utilizes ethylbenzene to make the hydroperoxide, which then is used to make propylene oxide [75-56-9]. The hydroperoxide-producing reaction is similar to the first step of cumene LPO except that it is slower (2,224,316—318). In the epoxidation step, a-phenylethyl alcohol [98-85-1] is the coproduct. It is dehydrated to styrene [100-42-5]. The reported 1992 capacity for styrene by this route was 0.59 X 10 t/yr (319). The corresponding propylene oxide capacity is ca 0.33 x 10 t/yr. The total propylene oxide capacity based on hydroperoxide oxidation of propylene [115-07-1] (coproducts are /-butyl alcohol and styrene) is 1.05 x 10 t/yr (225). 

In order for the cyclooxygenase to function, a source of hydroperoxide (R—O—O—H) appears to be required. The hydroperoxide oxidizes a heme prosthetic group at the peroxidase active site of PGH synthase. This in turn leads to the oxidation of a tyrosine residue producing a tyrosine radical which is apparendy involved in the abstraction of the 13-pro-(5)-hydrogen of AA (25). The cyclooxygenase is inactivated during catalysis by the nonproductive breakdown of an active enzyme intermediate. This suicide inactivation occurs, on average, every 1400 catalytic turnovers. 

Peroxides N,N-Dimethyl-1,4-phenylenediamine (N,N-DPDD), N,N,N, N -tetra-methyl-l,4-phenylene-diamine (TPDD) Peroxides, e. g. alkyl hydroperoxides, oxidize N,N-DPDD to Wurster s red and TPDD to Wurster s blue. [17] [34]... 

Peroxides, e.g. alkyl hydroperoxides, oxidize N.N-DPDD to Wurster s red and TPDD to Worster s blue. 

It seems very probable that the epoxidation reaction proceeds through a two-stage mechanism. Hydroperoxide oxidizes the catalyst to peroxo complex and the this complex performs epoxidation of olefins. 

GA Tolstikov. Reactions of Hydroperoxide Oxidation. Moscow Nauka, 1970 [in Russian]. 

During PP oxidation, hydroxyl groups are formed by the intramolecular isomerization of alkyl radicals. Since PP oxidizes through an intense intramolecular chain transfer, many of the alkyl radicals containing hydroperoxy groups in the 0-position to an available bond can undergo this reaction. An isomerization reaction has also been demonstrated for the liquid-phase oxidation of 2,4-dimethylpentane [89], Oxidation products contain, in addition to hydroperoxides, oxide or diol. 

Quasistationary (with respect to hydroperoxide) oxidation is possible for the mechanisms with a critical behavior (at [InH] > [InH]cr) as well as for ordinary mechanisms (at kdr > 1). 

Hydroperoxides oxidize aromatic amines more readily than analogous phenols. Thus, at 368 K cumyl hydroperoxide oxidizes a-naphthylamine and a-naphthol with ku = 1.4 x 10 4 and 1.7 x 10 5L mol-1 s 1, respectively [115,118], The oxidation of amines with hydroperoxides occurs apparently by chain mechanism, since the step of free radical generation proceeds much more slowly. This was proved in experiments on amines oxidation by cumyl hydroperoxide in the presence of /V,/V -diphcnyl-l, 4-phcnylcnediamine (QH2) as a radical acceptor [125]. The following reactions were supposed to occur in solution (80% decane and 20% chlorobenzene) ... 

The stoichiometry of this reaction is usually close to unity [6-9]. Thus, cumyl hydroperoxide oxidizes triphenyl phosphite in the stoichiometry A[ROOH]/A[Ph3P] from 1.02 1 to 1.07 1, depending on the proportion between the reactants [6], The reaction proceeds as bimolecular. The oxidation of phosphite by hydroperoxide proceeds mainly as a heterolytic reaction (as follows from conservation of the optical activity of reaction products [5,11]). Oxidation is faster in more polar solvents, as evident from the comparison of k values for benzene and chlorobenzene. Heterolysis can occur via two alternative mechanisms... 

As shown in Table 12,H202 and fBuOOH have been used frequently as oxygen donors in peroxidase-catalyzed sulfoxidations. Other achiral oxidants, e.g. iodo-sobenzene and peracids, are not accepted by enzymes and, therefore, only racemic sulfoxides were found (c.f. entries 34-36). Interestingly, racemic hydroperoxides oxidize sulfides to sulfoxides enantioselectively under CPO catalysis [68]. In this reaction, not only the sulfoxides but also the hydroperoxide and the corresponding alcohol were produced in optically active form by enzyme-catalyzed kinetic resolution (cf. Eq. 3 and Table 3 in Sect. 3.1). 

Oxidation of sulfides and sulfoxides using Oxone dispersed on silica gel or alumina was reported . A study of surface mediated reactivity of Oxone compared its reactivity with that of ferf-butyl hydroperoxide. Oxidation of sulfides to sulfones in aprotic solvents mediated by Oxone on wet montmorillonite or clay minerals proceeds in high yields. Interestingly, when Oxone on alumina is applied for selective oxidation of sulfides in aprotic solvents, the product distribution is temperature-dependent and sulfoxides or sulfones are obtained in good to excellent yields (equation 56) . ... 

IR spectrophotometry, 661, 662 TEARS assay, 667 hydroperoxide oxidation, 692 Upid hydroperoxides, 977-8 decomposition, 669 DNA adducts, 978-84 protein adducts, 984-5 ozone adducts, 734 ozonide reduction, 726 ozonization characterization, 737, 739 peroxydisulfate reactions, 1013, 1018 Alkali metal ozonides, 735-7 Alkaline peroxide process, pulp and paper bleaching, 623... 

C-H bond unreactive to insertion, 1160 hydroperoxide oxidation, 692 Cardamom peroxide, antimalarial, 190, 191 Cardiac hypertrophy, reactive oxygen species, 611... 

C-H bond unreactive to insertion, 1160 flavonoid, 548-9, 550 hydroperoxide oxidation, 692 a-hydroxylation, 519-21, 522-3 IR spectrophotometry, 662 oxidation of alkenes, 521-5 Baeyer-VilUger, 784-7 transition metal peroxides, 1108-14 a,/S-unsaturated, 199-202, 246-7, 285,... 

By analogy with Reaction 2 oxygen should be evolved from alkoxy hydroperoxide oxidation and a nonacidic diperoxide produced (Reaction... 

Heikes, B M. Lee, D. Jacob, R. Talbot, J. Bradshaw, H. Singh, D. Blake, B. Anderson, H. Fuelberg, and A. M. Thompson, Ozone, Hydroperoxides, Oxides of Nitrogen, and Hydrocarbon Budgets in the Marine Boundary Layer over the South Atlantic, J. Geophys. Res., 101, 24221-24234 (1996). 

Hydroperoxides and peroxides oxidize primary and secondary aliphatic amines to imines. Thus f-butyl hydroperoxide oxidizes 4-methyl-2-pentyl-amine to 2-(4-methylpentylidene)-4-methyl-2-pentylamine in 66% yield [29]. Di-r-butyl peroxide reacts in a similar manner [29]. However, this reaction is... 

Hydroperoxides oxidize aromatic amines more readily than analogous phenols. Thus, at 368 cumyl hydroperoxide oxidizes a-naphthylamine and a-naphthol with ku = 1.4 x 10 4... 

CHO - COOH. This hydroperoxide oxidizes aldehydes to carboxyjic acids in generally satisfactory yields. The oxidation is conducted in CH2Cl2Na2C03 or C lljOll-NaOH. The oxidant does not attack alcohols. The oxidation, as in epoxidations with 1, can be effected with H202 and a catalytic amount of 1. 

N-Oxides, sulfoxides, sulfones.2 The hydroperoxide oxidizes tertiary amines to N-oxidcs (60 95% yield) and sulfides to sulfoxides (1 equivalent) or to sulfones (2 equivalents). 

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