Tris methylsilane

Examples of photochemical methods of addition to acetylene derivatives are the addition of methyl disulfide to hexafluoro-2-butyne [7] (equation 8), of trifluaramethanethial to methyl propiolate [S] (equation 9), of methanethiol to trifluoromethylacetylene and hexafluoro-2-butyne [9] (equation 8), and of tri-methylsilane to tetrafluoropropyne [10. ... 

Diketones can be converted to a-keto enol ethers by treatment with an alkoxy tri-methylsilane ROSiMe3.616... 

The following procedure describes the preparation of (dimethylamino)tri-methylsilane (pentamethylsilylamine), a precursor used in the preparation of the dimethylamino fluoro phosphoranes. 

Cleavage of epoxides. Three laboratories have reported cleavage of epoxides with iodo- or bromotrimethylsilane and triethylamine to give (2-haloalkoxy)tri-methylsilanes in high yield. Terminal epoxides are cleaved mainly to I-halo-2-tri-methylsiloxyalkanes. The products can be dchydrohalogcnatcd (DBU) to give... 

The stereo- and regiospecificity of the addition of Al—H bonds to heteroatom-substituted acetylenes is determined by the conditions. The reaction of (l-alkynyl)tri-methylsilanes with i-Bu2AlH in ether gives the (E) isomer with Al and Si attached to the same carbon atom s , whereas in hydrocarbon solvent the E isomer, initially formed, isomerizes rapidly to give the (Z) isomer" ... 

A second new class of MAO mechanism-based inactivators, (aminoalkyl)tri-methylsilanes, have been reported by Silverman and Banik (114). The idea for this class of MAO inactivators is based on the known activation of the carbon-silicon bond toward homolytic cleavage reaction when the silicon atom is /3 to a radical cation (115, 116). The aminomethyl-, aminoethyl-, and (amino-propyl)trimethylsilanes are all pseudo-first-order time-dependent inactivators of beef liver MAO that reduce the flavin cofactor during the inactivation reaction. Since denaturation of the inactivated enzyme allows flavin leoxidation, covalent bond formation might be to an amino acid residue (114). The stabilities of the enzyme adducts from the (aminoalkyl)trimethylsilanes were found to be differ-... 

An interesting reaction is the addition of l-phenyl-2-TMS-acetylene to carbonyl compounds, e.g. cyclohexanone (113) in the presence of catalytic amounts of tetrabutyl-ammoniumfluoride to form, for instance, [l-(phenylethynyl)cyclohex-l-yloxy]tri-methylsilane (569) (equation 287)324. However, if 4-t-butylcyclohexanone (570) reacts... 

However, we have found several products that are consistent with some participation by ion-molecule reactions in product formation. The reactions of recoiling silicon atoms in mixtures of phosphine and tri-methylsilane produce some provocative minor products (26). 

Condensation of phosphorus pentachloride with aromatic compounds containing adjacent OH groups, gives spiran-type phosphoranes (6.491, 6.498). Condensation of phosphorus pentafluoride with o-phenylenedioxy bis tri-methylsilane also gives a spiran-type derivative (4.499). 

Attempted asymmetric hydrosilylation of 0-methylcinnamaldehyde with tri-methylsilane or phenyldimethylsilane resulted in formation of a mixture of optically inactive 1,4-and 1,2-adducts. 

Preparative Methods several methods for the preparation of bis[(trimethylsilyl)methyl]zinc have been reported. Addition of powdered anhydrous zinc(II) chloride to a solution of [(trimethylsilyl)methyl]magnesium chloride in diethyl ether at 0 °C and subsequent stirring for 4 days at room temperature affords the title compound in 90% yield after fractional distillation. A second route consists of the reaction of (iodomethyl)tri-methylsilane with zinc/copper couple (prepared by reduction of CuO with dihydrogen in the presence of zinc dust) at reflux for 3 h and affords the title compound in 56% yield. Bis[(trimethylsilyl)methyl]zinc can also be prepared quantitatively by reacting bis[(trimethylsilyl)methyl]mercury with an excess of zinc at ambient conditions. ... 

Palladium-Catalyzed Coupling. Palladium catalysis (eq 5) has been successfully applied to the coupling of (iodoethynyl)tri-methylsilane and acrylate esters. palladium(II) acetate (0.004 equiv.), reduced in situ to paUadium(0), in the presence of the aLk)uie, methyl acrylate, carbonate base, and a phase-transfer salt at 25 °C, gave a 40% yield of the coupled product. ... 

Similarly, through the use of [difluoro(phenylthio)methyl]tri-methylsilane or [difluoro(phenylseleno)methyl]trimethyl-silane treated with TBAT, in the presence of amides, imines, or aldehydes, the respective difluoromethylene phenylsulfide or difluoromethylene phenylselenide is produced (eq 19). 

GC-MS analysis after partial cleavage with boron tribromide and formation of tri-methylsilane derivatives is suggested for qualitative analysis of ethoxylates. Some differentiation of compounds is possible (25). 

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