Peroxides silyl

Bis (trimethyl silyl) peroxide (CH2)3SiOOSi(CH2)3 can be used with triflic acid (CF SO H) and acts as an effective hydroxylating agent of aromatics such as toluene, mesitylene and naphthalene (165). Sodium perborate (a safe and inexpensive commercial chemical) can be used in conjunction with the triflic acid to hydroxylate aromatics (166). [Pg.561]

This excellent method of oxidative cleavage (/) of carbon-silicon bonds requires that the silane carry an electronegative substituent (2), such as alkoxy or fluoro. Either hydrogen peroxide or mcpba may be used as oxidant, and the alcohol is produced with retention of configuration (3). Fluoride ion is normally a mandatory additive in what is believed to be a fluoride ion-assisted rearrangement of a silyl peroxide, as shown below ... [Pg.123]

Silyl enol ethers, 23, 77, 99-117,128 Silyl enolates, 77 Silyl peroxides, 57 Silyl triflate, 94 Silyl vinyl lithium, 11 (E)-l -Silylalk-1 -enes, 8 Silylalumimum, 8 Silylation, 94 reductive, 26 a-C-Silylation, 113 O-Silylation.99,100 / -SilyIketone, 54 non-cydic, 55 Silylmagnesium, 8 Silyloxydienes, 112 Sodium hexamethyldisilazide, 89 Sodium thiosulphate pentahydrate, 59 Stannylation, see Hydrostannylation Stannylethene, 11 (Z)-Stilbene, 70 (E)-Stilbene oxide, 70 /3-Styryltrimethylsilane, 141 Swern oxidation. 84,88... [Pg.169]

Vinylic lithium reagents (26) react with silyl peroxides to give high yields of silyl enol ethers with retention of configuration. Since the preparation of 26 from vinylic halides (12-37) also proceeds with retention, the overall procedure is a... [Pg.796]

Reaction betweeen vinylic lithium compounds and silyl peroxides... [Pg.1686]

Silyl peroxides containing a vinyl group have also been prepared by the same method. [Pg.780]

Alkyl(chloro)silyl peroxides 8 and alkyl alkoxysilyl peroxides are prepared by the alkyl hydroperoxidation of dichlorodiorganosilane (equations 13-15). [Pg.780]

The reaction of phenylethynyllithium with BTSP affords almost exclusively silane 29, while the reactions with sterically hindered tri(n-propyl)silyl and tri(n-butyl)silyl peroxides afford mixtures of silanes 29 and silyl ethers 30 (equation 47). [Pg.796]

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... [Pg.805]

TABLE 14. Oxidation rates of thioxane and Af,Af-dimethyl- ci-anisidine by silyl peroxides as compared to analogous carbon peroxide... [Pg.806]

IV. SYNTHESIS OF ALCOHOLS VIA HEXA- AND PENTACOORDINATE SILYL PEROXIDES... [Pg.808]

Carboxylic peroxides are long known and have been extensively employed in mechanistic and preparative applications. This is also valid for acyclic silyl peroxides, particularly the recently much used BTSP, which as a protected H2O2 exhibits marked advantages as oxidizing agent compared to the parent hydrogen peroxide. [Pg.814]

The simple cyclic silyl peroxide, l,l,4,4-teteramethyl-l,4-disila-2,3-dioxane, 75, was prepared by classical synthetic methodology from its corresponding cyclic disilazane 74 and the urea complex of H2O2 (equation 85) . [Pg.814]

Aerobic Co(II) catalysed hydroperoxysiiyiation of allylic alcohols provides silyl peroxides that can be condensed with ketones to produce 1,2,4-trioxanes or 1,2,4-trioxepanes by a simple one-pot procedure (Scheme 35A). A recent improvement in the use of Co(acac)2 is the use of Co(thd)2 (thd = bis (2,2,6,6-tetramethyl-3,5-heptanedionato)). This more reactive catalyst allows cyclic allylic alcohols to be oxygenated and the resulting peroxysilyl alcohol can be transformed to spiro trioxanes, some of which have potent in vitro antimalarial activity (Scheme 35B). For example, compound 87 expresses activity around 20 nM (artemisinin = 10 nM). [Pg.1330]

Bis(silyl) peroxide, preparation, 776-7 Bis(stannyl)peroxide, peroxide transfer reaction, 825... [Pg.1446]

Chlorotetramethyldisiloxane, preparation, 781 Chlorotriorganosilanes, silyl peroxide preparation, 779-83... [Pg.1450]

Conjugated dienes value (CDV), secondary oxidation products, 663, 671-2 Coordination compounds O NMR spectroscopy, 185 silyl peroxides, 808-10 Coordination ionospray mass spectrometry,... [Pg.1451]

Heteropoly acid, tungstate-based, 496, 497 Hexacoordinate silyl peroxides, 808-10 , -Hexa-2,4-diene, photooxidation, 254-5 Hexamethyldisiloxane, oxidation, 806-7 Hexamethylene triperoxide diamine (HMTD) enthalpy of formation, 166 explosive, 707-8... [Pg.1465]

Particle emissions, diesel fuel additive, 624 Partition number, conjugated dienes, 671 Pasteurization, lactoperoxidase, 612, 631, 634 Paterno-Buchi triplet 1,4-diradical, 290-1 PCPO see Bis(pentachlorophenyl) oxalate Pentacoordinate silyl peroxides, 808-10 Pentacosane, thermal oxidation, 685 O -Pentafluorobenzylhydroxyamine, aldehyde determination, 670... [Pg.1479]

Silanone, disilene oxidation, 821 Silicon peroxides see Silyl peroxides Silicotungstate compound, olefin epoxidation,... [Pg.1488]

Silyl hydrotrioxides, silane ozonolysis, 812 Silyl peroxides, 776-821... [Pg.1488]

Triaryl phosphite-ozone adducts, 706 Tri( -butyl)silyl peroxides, bis(trimethylsilyl) peroxide reactions, 796 Trichloroacetyl chloride, from tetrachloroethene, 731... [Pg.1494]

To develop new electrophilic reagents, Ricci and coworkers have described the synthesis of trimethylsilyloxy and hydroxy compounds from magnesium enolates and bis(trimethyl-silyl)peroxide. Magnesium enolates, generated using magnesium diisopropylamide, (DA)2Mg, give the hydroxycarbonyl compounds in excellent yields (equation 72, Table 8). [Pg.475]

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