Oxidations with Bis trimethylsilyl peroxide

Although bis(trimethylsilyl)peroxide (BTSP) 1949 is considered in a review to be quite stable [137], some minor accidents with its use have been reported [138]. It is usually prepared from 85% H2O2 and Me3SiCl (TCS) 14 in ether-pyridine 

Combination of BTSP 1949 with TMSOTf 20 [157], with sulfur trioxide SO3 (which, with BTSP 1949, forms Me3Si02S020SiMe3 1982 [158]), or with SnCU 

The combination of BSTP 1949 with SnCl4 converts olefins such as cyclopen-tene 1991a, cyclohexene 1991b, or cycloheptene 1991c into their trans-l,2-chloro-hydrins 1992 a-c in 74, 85 and 92% yield, respectively [168]. Reaction of the cyclic 

Kinetic studies of the oxidation of phosphites such as triisopropyl phosphite with BTSP 1949 to give phosphates such as triisopropyl phosphate [177] led to the discovery that oxidation of diphosphite nucleotide intermediates such as 2008 with BTSP 1949 at -20 °C in the presence of TMSOTf 20 (instead of iodine in 

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Startg. vinyl bromide treated with 1 eq.. sec-butyllithium in THE at —78, and oxidized with bis(trimethylsilyl) peroxide after 15 min product. Y 75%. The method permits the generation of ketone enolates in a regio- and stereo-defined manner, and is especially useful for ketone derivs. where the two a-sites are similar. F.e.s. F.A. Davis et al., Tetrahedron Letters, 29, 4269-72 (1988) f.e.s. L. Camici et al., Tetrahedron 44, 4197-206 (1988). 

Yudin and Sharpless reported on the utilization of much cheaper, readily available inorganic Re catalysts [Re207, ReOsfOH), ReOs (0.5-1 mol%)] in combination with bis(trimethylsilyl) peroxide as oxidant and 0.5-1 mol% of pyridine (equation 52) . In this oxidation process high epoxide yields (78-96%) were obtained using CH2CI2 or THF as solvent. Traces of water or other protic species have been found to be essential for rapid turnover and accelerate the reaction. 

Silicon and gennaninm peroxides TABLE 15. Oxidation of disilanes with bis(trimethylsilyl) peroxide... 

It is possible to use PDC as a catalytic oxidant (10 mol %), with bis(trimethylsilyl) peroxide as the cooxidmt, for the preparation of carbcmyl compounds. It is necessary to add the cooxidant slowly via syringe pump since the actual oxidizing agent (15) is unstable in solution. A range of primary and secondary alcohols were oxidized in good yields by this method (Table 14). Fortunately, isolated double bonds are inert under these conditions. 

The Baeyer-Villiger oxidation of ketones with bis(trimethylsilyl)peroxide 74 is effected by use of catalytic amounts of la [86]. In particular, cyclic ketones are readily converted to the corresponding lactones in good yields although the attempted oxidation of alkyl phenyl ketones failed. This present reaction is also chemo- and regio-selectively useful. For instance, bicyclo[3.2.0]hept-2-en-6-one 75 upon exposure to 74 and 10 mol % of la leads exclusively to prostaglandin intermediate 76 in 75 % yield (Sch. 50). 

Chemical oxidation is achieved with bis(trimethylsilyl) peroxide in the presence of trimethylsilyl trifluoroacetate (triflate). Androsterone acetate is converted into androstenolactone acetate in 86% yield (equation 396) [237. ... 

Lithiofuran, best obtained fj-om 3-bromofuran, reacts with bis(trimethylsilyl)-peroxide to provide the trimethylsilyl ether of 3-hydroxyfuran directly. Oxidation of a 2-boronate ester is a means for the synthesis of butenolides (section 15.13.1). Furan-2- and 3-boronic acids have been made by reaction of the lithiated species with tributylborate in the usual way. ... 

Bis(trimethylsilyl)peroxide (1) can be used to produce phosphine oxides stereospecifically from either phosphines (with retention) or phosphine sulphides (with inversion).1 A variety of organoelement substituted pentadienes, including the phosphine oxides (2) and (3),... 

The oxidation of substituted pyridines to iV-oxides was reported by Sharpless and coworkers to proceed with yields between 78 and 99% (Scheme 154). A variety of substituents like electron donor as well as acceptor groups and alkenyl substituents are tolerated. In 1998, Sharpless and coworkers reported an alternative method for the preparation of pyridine-A-oxides in which the MTO/H2O2 catalyst could be replaced by cheaper inorganic rhenium derivatives (ReOs, Re207, HOReOs) in the presence of bis(trimethylsilyl) peroxide (equation 73). Yields of the prepared A-oxides after simple workup (filtration and bulb to bulb distillation) ranged from 70-98%. Molecular sieves slowed down the reaction while small amounts of water (0-15%) were essential for the reaction. Both electron-poor or electron-rich pyridines give high yields of their A-oxides and while para-... 

Information of the Gif system has been summarized,1055 1123 and new results, including new oxidants such as bis(trimethylsilyl) peroxide,1124 the synergistic oxidation of saturated hydrocarbons and H2S,1125 studies with the Fe3+-picolinate complex encapsulated within zeolites,1126 and the use of Udenfriend s system under Gif conditions1127 were disclosed. Gif-type oxidations were found to be moderately stereoselective.1128 Iron/zinc-containing species involved in Gif-type chemistry were synthesized, and their reactivity and catalytic behavior were studied.1129... 

Direct conversions of sulfones to carbonyl compounds have been realized by oxidative desulfonation of the a-carbanions. Molybdenum peroxide (Mo05-Py-HMPA) [266], or bis(trimethylsilyl)peroxide (Mc3SiOOSiMej, BTSP, Table 3.3) [267] were used as oxidants. Hwu s method with BTSP is attractive and was found useful for the preparation of 180-Iahelled compounds [267] in this one-pot reaction Me3SiO behaves as a leaving group and a back-attacking species. 

With perbenzoic acid or bis(trimethylsilyl)peroxide, oxidation of the Si—Si bond occurs ... 

With peroxybenzoic acid or bis(trimethylsilyl)peroxide, II can be oxidized to cis-l,6-dimethyl-II-oxa-l,6-disila-[4,4,l]-undecane (III). This compound can be obtained only in the cis form since in the trans form the ring straining is too great... 

Oxidation of vinyllithiums.2 Vinyllithiums are oxidized to silyl enol ethers by bis(trimethylsilyl) peroxide (1) with retention of configuration. Yields can be increased by use of bis(f-butyldimethylsilyl) peroxide (2). 

Bis(trimethylsilyl) peroxide, (CH3)3SiOOSi(CH3)3, is prepared from trimethylsilyl chloride, l,4-diaza[2,2,2]bicyclooctane, and Dabco s complex with 2 mol of hydrogen peroxide [127]. It is used alone [228] or in the presence of catalysts such as pyridinium dichromate [236] trimethylsilyl trifluoromethanesulfonate, CF3S03Si(CH3)3 [228, 237] or tris-(triphenylphosphine)ruthenium dichloride, [(C6H5)3P]3RuCl2 [236]. This reagent oxidizes primary alcohols to aldehydes (in preference to the oxidation of secondary alcohols to ketones [236]), ketones to esters or lactones Baeyer-Villiger reaction) [238], and nucleoside phosphites to phosphates [228]. All these oxidations require anhydrous conditions. 

Oxidation of alkenyllithiums with bis(trimethyisilyi)peroxide gives trimethylsilyl enol ethers, which may be easily hydrolyzed to the corresponding ketones [47]. 

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