Terf-Butyl hydroperoxide

Rate law and activation energy. The oxidation of nitrosobenzene by terf-butyl hydroperoxide is catalyzed by di-terf-butyl peroxyoxalate (TBO) and by a cobalt(II) chelate complex. 

Peroxy esters 67 were prepared in situ by the reaction of phosphonochloridate and terf-butyl hydroperoxide in diethyl ether. The peroxy ester 67 (R = Ph) is stable for several days at 5 °C in diethyl ether. Most peroxyphosphates 67 with an RO group other than ferf-butylperoxy are unstable even for short periods . This synthetic method was successfully applied for synthesis of ring peroxyphosphates 70 and 71 as colorless oils. They are very unstable and decompose at 25 °C to yield polymeric products and volatile side products . ... 

Peroxyphosphonate can be prepared by a similar reaction in the presence of pyridine instead of the sodium salt of the hydroperoxide. Peroxyphosphonates 72 are generally synthesized by the condensation of the corresponding phosphinic chloride with the sodinm salt of terf-butyl hydroperoxidate in a neutral solvent in the presence of sodinm snlfate, or alternatively, by the reaction of terf-butyl hydroperoxide with phosphinic chloride in the presence of pyridine . 

Di-te/7-butyl peroxide (te/7-butyl peroxide) [110-05-4] M 146.2, d 0.794, n 1.3889. Washed with aqueous AgNC>3 to remove olefinic impurities, water and dried (MgSO. Freed from terf-butyl hydroperoxide by passage through an alumina column [Jackson et al. JACS 107 208 1985], and if necessary two high vacuum distns from room temp to a liquid-air trap [Offenbach and Tobolsky JACS 79 278 1957]. The necessary protection from EXPLOSION should be used. 

Little can be said about the pre-exponential factor. It is lower than that reported by Kirk and Knox (20) for the decomposition of ethyl and terf-butyl hydroperoxide, but it is still in the expected range for a uni-molecular fragmentation into two radicals (9). 

Three additional experiments were carried out at 30°C using only 5 mL of terf-butyl hydroperoxide (70% solution in water, 36.4 mmol) instead of 8 mL. The reaction data collected from all six experiments at 30°C were then concatenated to a second Aoata matrix and a second qDaU vector. The experimental procedure is described in further detail elsewhere [20]. 

Examples of molecular sieve incidents other than the subentries Benzyl bromide, Molecular sieve, 2731 terf-Butyl hydroperoxide, Molecular sieves, 1692 Mercury(II) perchlorate. 6 (or 4)dimethyl sulfoxide, 4073 Nitromethane, Molecular sieve, 0455 Oxygen difluoride, Adsorbents, 4311 1,1,1-Trichloroethane, 0737... 

Japanese scientists believe that the anti-oketsu effects of rhubarb are brought about by the inhibition of the production of nitric oxide, inhibition of platelet aggregation, antiallergic effects, and its antiinflammatory properties. Matsuda et al. (2001) studied and reported that the methanolic extracts from five kinds of rhubarb were found to show scavenging activity for l,l-diphenyl-2-picrylhy-drazyl (DPPH) radical and superoxide anion radical (02 ) generated by the xanthine/xanthine oxidase system and/or on lipid peroxidation by terf-butyl hydroperoxide (f-BuOOH) in the erythrocyte membrane ghost system. 

At the same time the curved arrows in Figure 3.41 explain the kind of diastereoselectivity observed with the oxygen transfer from terf-butyl hydroperoxide to the respective allylic alcohol. The first stereoformulas of the resulting epoxy alcohol each emulate the transition state geometry. The second stereoformulas of the resulting epoxy alcohol each ensure comparability to the formulas for the products of Figures 3.39 and 3.40. 

Co(modp)2 338a, oxygen, terf-butyl hydroperoxide, and isopropanol to 2-hydroxymethyltetrahydrofurans 419 in 53-79% yield with exclusive trans-selectivity [442]. Reduced tetrahydrofurans 420 were isolated as a side product. This method was applied in total syntheses of annonaceous acetogenins [443], such as gigantetrocin A [444, 445], asimilobin [446, 447], mucocin [448, 449], or bullatacin [450], as well as of the algal natural product aplysiallene [451]. 

Recently An et al. disclosed a palladium(II)-catalyzed bis(peroxidation)/cycli-zation method for the synthesis of 3-(peroxymethyl)-3-peroxyoxindoles 209 from N - ar y 1 aery I a m i d e s 208 (Fig. 52) [235]. Using 5 mol% of Pd(OAc)2 in the presence of terf-butyl hydroperoxide, 46-96% of products 209 were obtained. The reactions were proposed to involve a Pd-catalyzed radical bis(peroxidation) of the acrylic unit [236] followed by a two-electron directed cyclometalation/reductive elimination reaction of intermediate bis(peroxide) 208A. 

A solution containing 5.0 X 10 2 mole/liter terf-butyl hydroperoxide and 2.5 X 10 2 mole/liter dilauryl thiodipropionate was allowed to react at 80 °C. until no hydroperoxide remained. A slight precipitate was obtained which could not be identified. Vapor phase chromatography of the residual solution at 100°C. on a column containing 20% w/w di-n-decyl phthalate on 60-80 mesh C22 firebrick gave tert-butyl alcohol as the main identifiable product. 

Addition of aryl tellurium trihalides to cyclohexene produces trails-] -aryldihalotelluro-2-halocyclohexanes when the reactions are carried out in chloroform, and trans-1-aryldihalotelluro-2-methoxycyclohexanes when methanol is used as the reaction medium. Treatment of the 2-chlorocyclohexyl 4-methoxyphenyl tellurium dichloride with terf.-butyl hydroperoxide in acetic acid yielded tram-l,2-dichlorocyclohexane and aryl chloride. Bis[4-methoxyphenyl] tellurium dichloride did not yield any aryl chloride under these conditions1. Pyrolysis of tran.s-2-methoxycydohexyl phenyl tellurium dibromidc afforded Crum- l-bromo-2-methoxycyclohexane1. 

Osmium tetroxide was supplied by Matthey-Bishop, Inc. in 1-g amounts in sealed glass ampuls. The procedure that we describe below should be followed to prepare the osmium tetroxide catalyst solution. Work in a well-ventilated hood. One ampul is scored in the middle, broken open, and the two halves are dropped into a clean, brown bottle containing 39.8 mL of reagent grade terf-butyl alcohol and 0.20 mL of 70 or 90% terf-butyl hydroperoxide (Aldrich). The bottle is capped (use caps with Teflon liners) and then swirled to ensure dissolution of the Os04. These solutions are stored in the hood at room temperature and seem to be very stable. 

Most Sharpless asymmetric epoxidations have been conducted in dichloromethane since this solvent was that initially employed. Other solvents that have been successfully used are toluene, heptane and isooctane. Due to the stability in storage of terf-butyl hydroperoxide in isooctane this solvent is now recommended, with dichloromethane and toluene as the next choices42. 

A flask is cooled to — 20 °C and 1.24 g (6.0 mmol) of ( + )-diethyI L-tartrale and 1.49 mL (1.42 g, 5.0 mmol) of titanium(IV) isoproxide are added sequentially by syringe with stirring. The reaction mixture is stirred at — 20 °C as 39 mL (200 mmol, 5.17 M in isooctanc) of terf-butyl hydroperoxide are added through the addition funnel at a moderate rate (over ca. 5 min). The resulting mixture is stirred at — 20 °C for 30 min. 12.82 g (100 mmol) of freshly distilled ( )-2-octenol, dissolved in 50 mL of CH,C12, are then added drop-wise through the same addition funnel over a period of 20 min, being careful to maintain the reaction temperature between —20° to — 15°C. The mixture is stirred for an additional 3.5 h at —20° to —15 °C. The workup procedure as above with iron(II) sulfate solution yields the epoxy alcohol (12.6 g, 88% crude yield, 92.3% cc by GC) which upon two rccrystallizations from petroleum ether (bp 40- 60°C) at — 20°C gives the product yield 10.5 g (73%) >98% ee. 

A similar increase in reactivities in the methyl-methylene-methine series is found in the free-radical oxidations of lower alkanes with oxygen in the presence of hydrogen bromide as an initiator of the reaction. Ethane gives a 64% yield of acetic acid at 220 °C, propane gives a 72% yield of acetone at 189 °C, and isobutane gives a 69.5% yield of terf-butyl hydroperoxide, a 10% yield of fm-butyl alcohol, and a 6% yield of di-rm-butyl peroxide at 163 °C [54],... 

Vinylcyclohexene and terf-butyl hydroperoxide, in the presence of chromium acetylacetonate, yield exclusively 4-vinylcyclohexene oxide [217]. 

Methylselenoxy analogs are even more difficult to react and treatment of the corresponding methylseleno derivative at 80 °C with terf-butyl hydroperoxide/basic alumina (conditions which proved particularly efficient for the synthesis of terminal olefins from methyl selenides bearing a methylseleno group at the terminus of the alkyl chain 7,8,12>, which are more difficult to react) as expected 140) does not lead 35) to the desired alkylidene cyclopropanes but to low yields of cyclobutanones resulting probably from the well-known 140) reaction of rert-butyl hydroperoxide with the alkylidene cyclopropane formed transiently35). 

In the field of asymmetric oxidation reactions the epoxidation of a,P-unsatu-rated carbonyl compounds was investigated. In the case of 1,4-naphthoquinone derivatives and terf-butyl hydroperoxide as reagents enantioselectivities up to 78% ee were observed with quininium and quinidinium salts as PT catalysts [40]. 

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