F-Butyl hydroperoxide

That observed for TS-1 is not peculiar for TS-1 only and can be observed on other titanosilicates like Ti-MSA, a mesoporous amorphous material that has Ti(Vl) centers exposed on the surface of the pores [124,125]. In this case, easier experiments could be performed by Prestipino et al. [50] as the peroxo/hydroperoxo complexes can be formed by dosing f-butyl hydroperoxide (which does not enter the 10-membered rings of TS-1). The XANES spectrum of Ti-MSA in vacuum is typical for almost r -like Ti(IV) centers (the intensity of the Ai T2 pre-edge peak being only 0.69, as compared with 0.91 for TS-1). Upon dosing the t-butyl hydroperoxide in decane solution on Ti-MSA, a spectrum similar to that obtained on TS-1 contacted with anhydrous H2O2 is observed on both XANES and EXAFS regions [50]. When the... 

Transition Metal-Catalyzed Epoxidation of Alkenes. Other transition metal oxidants can convert alkenes to epoxides. The most useful procedures involve f-butyl hydroperoxide as the stoichiometric oxidant in combination with vanadium or... 

The elimination is promoted by oxidation of the addition product to the selenoxide by f-butyl hydroperoxide. The regioselectivity in this reaction is such that the hydroxy group becomes bound at the more-substituted end of the carbon-carbon double bond. The regioselectivity of the addition step follows Markovnikov s rule with PhSe+ acting as the electrophile. The elimination step specifically proceeds away from the oxygen functionality. 

Another interesting asymmetric epoxidation technique using metal catalysis involves the vanadium complexes of A-hydroxy-[2.2]paracyclophane-4-carboxylic amides (e.g., 19), which serve as catalysts for the epoxidation of allylic alcohols with f-butyl hydroperoxide as... 

Oxirane A general process for oxidizing olefins to olefin oxides by using an organic hydroperoxide, made by autoxidation of a hydrocarbon. Two versions are commercial. The first to be developed oxidizes propylene to propylene oxide, using as the oxidant f-butyl hydroperoxide made by the atmospheric oxidation of isobutane. Molybdenum naphthenate is used as a... 

Oxidative coupling of alkenylstannanes.3 1-Alkenylstannanes undergo homocoupling to 1,3-dienes when treated with f-butyl hydroperoxide in the presence of catalytic amounts of Pd(OAc)2. Under these conditions 1-alkenylstannanes couple with 2-aIkenyIstannanes to give 1,4-dienes. 

The oxidative procedure is based on the treatment with oxidants, preferably f-butyl hydroperoxide in refluxing dioxane, acetic acid or acetonitrile. 

The initiators used in emulsion polymerization are water-soluble initiators such as potassium or ammonium persulfate, hydrogen peroxide, and 2,2 -azobis(2-amidinopropane) dihydrochloride. Partially water-soluble peroxides such a succinic acid peroxide and f-butyl hydroperoxide and azo compounds such as 4,4 -azobis(4-cyanopentanoic acid) have also been used. Redox systems such as persulfate with ferrous ion (Eq. 3-38a) are commonly used. Redox systems are advantageous in yielding desirable initiation rates at temperatures below 50°C. Other useful redox systems include cumyl hydroperoxide or hydrogen peroxide with ferrous, sulfite, or bisulfite ion. 

In order to obtain good yields, it is important to use dry solvent and reagents. The commercially available f-butyl hydroperoxide contains about 30% water for stabilization. For the use in a Sharpless epoxidation reaction the water has to be removed first. The effect of water present in the reaction mixture has for example been investigated by Sharpless et al. for the epoxidation of (E)-a-phenylcinnamyl alcohol, the addition of one equivalent of water led to a decrease in enantioselectivity from 99% e.e. to 48% e.e. 

Dimethyl-2-hydroperoxide-5-ierr-butylperoxyhexane contains both a peroxy and a hydroperoxy group. The enthalpy of reaction 5, to give 2,5-dimethyl-2-hydroxy-5-f-butylperoxyhexane, is —59.9kJmoR (Iq) and —58.8kJmol (g), comparable to those obtained from 1-methylcyclohexane hydroperoxide and f-butyl hydroperoxide. If the mixed peroxide were to undergo the formal reactions 5 and 6 simultaneously, the alcohol product would be 2,5-dimethylhexane-2,5-diol, for which there is only an enthalpy... 

Hydroperoxides undergo reduction with aqueous Fe(II), which turns to aqueous Fe(III). The reaction can be followed at 305 nm (e = 2095 M cm ) ° . Although the stoichiometry of this process is straightforward, with two Fe(II) ions being consumed per molecule of hydroperoxide, the mechanism involves an alkoxide free radical, RO", that may undergo -elimination, H abstraction from R—H, or a 1,2-H-shift and reaction with other components in the system. A case in point is the determination of f-butyl hydroperoxide which consumes under 1 mol of Fe(II) per mol of analyte under inert gas cover, while in the presence of O2 four mols are consumed, pointing to extensive side reactions of the RO" free radical, both without and with O2 in the system. ... 

In the presence of diisopropyl(ethyl)amine, tetrachlorosilane reacts with f-butyl hydroperoxide to give 1 1 adduct 9 (equation 16). Alkylperoxydiorganoalkoxysilanes are prepared from the reaction of chlorodiorganooxysilane with alkyl hydroperoxides in the presence of ammonia or organic base such as pyridine or triethylamine (equations 17 and 18). 

The reaction of l,3-dichloro(tetramethyl)siloxane 12 with f-butyl hydroperoxide in the presence of pyridine in ether gave l-f-butylperoxy-3-chlorotetramethyldisiloxane 13 in 60% yield (equation 19). 

A less frequently used method involves the condensation of trimethylsilyl alkylamines with f-butyl hydroperoxide. A 20% yield of trunethyl(f-butylperoxy)silane has been obtained (equation 26). ... 

Oxidation of 1,4-thioxane by BTSP and f-butyl(trimethylsilyl) peroxide in CHCI3 at 25 °C is compared to those of the same substrate by the more common oxidants, f-butyl hydroperoxide and di-f-butyl peroxide, in the same solvent. The two silyl peroxides give similar oxidations rates, which are over 50 times higher than that measured for f-BuOOH, while f-Bu202 is almost unreactive under the conditions adopted. Oxidation... 

The oxidizing agents most frequently used are hydrogen peroxide, MCPBA or peracetic acid. Additional fluoride (KF and/or KHF2) is required in many, but not aU, existing protocols. Basic conditions (KH, f-butyl hydroperoxide and TBAF) have been employed as... 

Transition metal-catalyzed epoxidations, by peracids or peroxides, are complex and diverse in their reaction mechanisms (Section 5.05.4.2.2) (77MI50300). However, most advantageous conversions are possible using metal complexes. The use of f-butyl hydroperoxide with titanium tetraisopropoxide in the presence of tartrates gave asymmetric epoxides of 90-95% optical purity (80JA5974). 

Recently (79MI50500) Sharpless and coworkers have shown that f-butyl hydroperoxide (TBHP) epoxidations, catalyzed by molybdenum or vanadium compounds, offer advantages over peroxy acids with regard to safety, cost and, sometimes, selectivity, e.g. Scheme 73, although this is not always the case (Scheme 74). The oxidation of propene by 1-phenylethyl hydroperoxide is an important industrial route to methyloxirane (propylene oxide) (79MI5501). 

The molybdenum-catalyzed oxidation of alkynes by f-butyl hydroperoxide has been investigated (73JCS(Pl)285l) (the epoxidation of alkenes by this system has become an important reaction Section 5.05.4.2.20 )) but the formation of oxirenes was excluded. 

Treatment of 2-methylthiirane with f-butyl hydroperoxide at 150 °C in a sealed vessel gave very low yields of allyl disulfide, 2-propenethiol and thioacetone. The ally derivatives may be derived from abstraction of a hydrogen atom from the methyl group followed by ring opening to the allylthio radical. Percarbonate derivatives of 2-hydroxymethylthiirane decompose via a free radical pathway to tar. Acrylate esters of 2-hydroxymethylthiirane undergo free radical polymerization through the double bond. 

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... 

Tertiary alkyl primary amines can be oxidized to nitro compounds in excellent yields with KMn04.39S This type of nitro compound is not easily prepared in other ways. All classes of primary amine (including primary, secondary, and tertiary alkyl as well as aryl) are oxidized to nitro compounds in high yields with dimethyldioxirane.399 Other reagents that oxidize various types of primary amines to nitro compounds are dry ozone,4,111 various peracids,401 including peracetic and peroxytrifluoroacetic acids, f-butyl hydroperoxide in the presence of certain molybdenum and vanadium compounds,402 F7-H20-MeCN,41123 and sodium perborate.403... 

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