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T Butyl hydroperoxide

Table 4. Solvents for Purification of Propylene Oxide From Epoxidation Using fe/t-Butyl Hydroperoxide... Table 4. Solvents for Purification of Propylene Oxide From Epoxidation Using fe/t-Butyl Hydroperoxide...
When heated in the presence of a carboxyHc acid, cinnamyl alcohol is converted to the corresponding ester. Oxidation to cinnamaldehyde is readily accompHshed under Oppenauer conditions with furfural as a hydrogen acceptor in the presence of aluminum isopropoxide (44). Cinnamic acid is produced directly with strong oxidants such as chromic acid and nickel peroxide. The use of t-butyl hydroperoxide with vanadium pentoxide catalysis offers a selective method for epoxidation of the olefinic double bond of cinnamyl alcohol (45). [Pg.175]

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 t-butyl hydroperoxide with titanium tetraisopropoxide in the presence of tartrates gave asymmetric epoxides of 90-95% optical purity (80JA5974). [Pg.36]

Treatment of 2-methylthiirane with t-butyl hydroperoxide at 150 °C in a sealed vessel gave very low yields of allyl disulfide, 2-propenethiol and thioacetone. The allyl 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. [Pg.167]

SHARPLESS Asymmetne Epoxidation EnanlioselectK/e epoxidation of altyl alcohois by means of Irtanlum a5(oxide, (+) or () diethyl tartarate (OET) and t butyl hydroperoxide (TBHP)... [Pg.343]

Preparation of (Me0)2P-0-R ROH, (MeO)3P, CBr4, Pyr, 70-98% yield. The alkyl dimethyl phosphite may then be oxidized to the corresponding phosphate by aq. iodine, t-butyl hydroperoxide, or peracid. [Pg.666]

In order to obtain good yields, it is important to use dry solvent and reagents. The commercially available t-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. [Pg.256]

Dione 21-Acetate To a stirred solution of 500 mg of 9o-fluoro-11(3,21-dihydroxy-16-methyl-1,4,16-pregnatriene-3,20-dione 21-acetate in 5 ml of benzene and 5 ml of chloroform are added 0.50 ml of t-butyl hydroperoxide and 0.1 ml of a 35% methanolic solution of benzyl-trimethyl ammonium hydroxide. After 18 hours at room temperature, water is added and the mixture thoroughly extracted with chloroform. The chloroform extract is washed with saturated aqueous sodium chloride and dried over magnesium sulfate. Evaporation of the Solvent and crystallization of the residue from acetone-ether gives Bo-fluoro-... [Pg.684]

The common initiators of this class are f-alkyl derivatives, for example, t-butyl hydroperoxide (59), Aamyl hydroperoxide (60), cumene hydroperoxide (61), and a range of peroxyketals (62). Hydroperoxides formed by hydrocarbon autoxidation have also been used as initiators of polymerization. [Pg.92]

Paraplex Propallants. A series of JATO proplnts (the PF-series) developed by the Aerojet Engrg Corp, Azusa, Calif using Paraplex P-10 resin-styrene mixt as a fuel ingredient in the amt of approx 26.5%. Other ingredients are AN or K perchlorate, 73.0%, and small amts of t-butyl-hydroperoxide or benzoylperoxide, 0.1 to 0.5% (as a polymerization catalyst) (Ref 2)... [Pg.489]

Colona and coworkers oxidized a variety of alkyl aryl and heterocyclic sulfides to the sulfoxides using t-butyl hydroperoxide and a catalytic amount of a complex (97) derived from a transition metal and the imines of L-amino acids. Of the metals (M = TiO, Mo02, VO, Cu, Co, Fe), titanium gave the highest e.e. (21%), but molybdenum was the most efficient catalyst. The sulfoxides were accompanied by considerable sulfone125. [Pg.75]

Other metals can also be used as a catalytic species. For example, Feringa and coworkers <96TET3521> have reported on the epoxidation of unfunctionalized alkenes using dinuclear nickel(II) catalysts (i.e., 16). These slightly distorted square planar complexes show activity in biphasic systems with either sodium hypochlorite or t-butyl hydroperoxide as a terminal oxidant. No enantioselectivity is observed under these conditions, supporting the idea that radical processes are operative. In the case of hypochlorite, Feringa proposed the intermediacy of hypochlorite radical as the active species, which is generated in a catalytic cycle (Scheme 1). [Pg.45]

Dimethyl peroxide Diethyl peroxide Di-t-butyl-di-peroxyphthalate Difuroyl peroxide Dibenzoyl peroxide Dimeric ethylidene peroxide Dimeric acetone peroxide Dimeric cyclohexanone peroxide Diozonide of phorone Dimethyl ketone peroxide Ethyl hydroperoxide Ethylene ozonide Hydroxymethyl methyl peroxide Hydroxymethyl hydroperoxide 1-Hydroxyethyl ethyl peroxide 1 -Hydroperoxy-1 -acetoxycyclodecan-6-one Isopropyl percarbonate Isopropyl hydroperoxide Methyl ethyl ketone peroxide Methyl hydroperoxide Methyl ethyl peroxide Monoperoxy succinic acid Nonanoyl peroxide (75% hydrocarbon solution) 1-Naphthoyl peroxide Oxalic acid ester of t-butyl hydroperoxide Ozonide of maleic anhydride Phenylhydrazone hydroperoxide Polymeric butadiene peroxide Polymeric isoprene peroxide Polymeric dimethylbutadiene peroxide Polymeric peroxides of methacrylic acid esters and styrene... [Pg.163]

Figure 1. Influence of T1O2 content of LT-aerogels on relative proportion of Si-O-Ti connectivities R = [Si-0-Ti]/(Si-0-Si], mean pore diameter, and initial rate (to) of a-iso-phorone ep>oxidation with t-butyl hydroperoxide at 60 C. Data taken from ref. [18]. Figure 1. Influence of T1O2 content of LT-aerogels on relative proportion of Si-O-Ti connectivities R = [Si-0-Ti]/(Si-0-Si], mean pore diameter, and initial rate (to) of a-iso-phorone ep>oxidation with t-butyl hydroperoxide at 60 C. Data taken from ref. [18].
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... [Pg.63]

Oxidative cleavage of oxosulfonium ylides as well as of sulfoximines leads to sulfone formation. In the course of oxidations of dialkoxy sulfuranes(IV) by hydrogen peroxide" or t-butyl hydroperoxide , sulfone formation takes place (equation 99). [Pg.219]

Benzoyl hydroperoxide was used for the conversion of divinyl sulphide into divinyl sulphoxide by Levin as early as 1930. In 1954 Bateman and Hargrave reported that saturated sulphides may be oxidized to sulphoxides by means of cyclohexyl or t-butyl hydroperoxide. These authors found that in both polar and non-polar solvents oxygen transfer occurred to give quantitative yields of sulphoxides over a wide range of experimental conditions according to equation 7. It was also reported that a quantitative yield of sulphoxides was obtained from the reaction of unsaturated sulphides with t-butyl and cyclohexyl hydroperoxides in methanol. With t-butyl hydroperoxide in benzene the sulphoxide yield was in no case stoichiometric, varying from 90 to 5% under the condition chosen. [Pg.240]

Two polymer-supported reagents have been developed for the oxidation of sulphoxides to sulphones these involve peracid groups , and bound hypervalent metals activated by t-butyl hydroperoxide . ... [Pg.985]

The effects of ROMs on liver have already been discussed. That iron is involved in such effects is indicated by the prevention of cell damage by t-butyl hydroperoxide by... [Pg.157]

Younes, M. and Strubelt, O. (1990). The role of iron and glutathione in t-butyl hydroperoxide-induced damage towards isolated perfused rat livers. J. Appl. Toxicol. 10, 319-324. [Pg.174]

Organic peroxides such as cumene hydroperoxide and t-butyl hydroperoxide have extensively been used as experimental agents. They provoke lipid peroxidation in hepatocytes, probably by the generation of alkoxyl and peroxyl radical intermediates after reaction with cytochrome P450. Other cytotoxic mechanisms are probably involved including protein thiol and non-protein thiol oxidation and deranged calcium homeostasis (Jewell et al., 1986). In fact, the addition of cumene hydroperoxide to isolated bUe duct cells, devoid of cytochrome P450 activity, still results in cell death but lipid peroxidation is not detectable (Parola et al., 1990). [Pg.241]

Finally, with the aim of discovering novel chiral oxomolybdenum catalysts able to perform enantioselective alkene epoxidations, Kuhn et al. have reported the exploration of the catalytic behaviour of a series of dioxomolybdenum(VI) complexes with chiral cw-8-phenylthiomenthol ligands derived from ( + )-pulegone. Therefore, the epoxidation of c -p-methylstyrene using t-butyl-hydroperoxide as the oxidant and performed in the presence of ( + )-(2i ,5i )-2-[1-methyl-l-(phenylthio)ethyl]-5-methylcyclohexanone oxime as the ligand, did not produce, however, a significant optical induction in these conditions. [Pg.326]


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Butyl hydroperoxide

T Butyl hydroperoxide (TBHP

T-BUTYL HYDROPEROXIDE.302(Vol

T-butyl

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