Silanes oxidations, dimethyldioxirane

Enolization of racemic ketone 122 with the chiral lithium amide 123 produced a mixture of regioisomeric enol silanes 124 and 125 [78]. A treatment with PhSeCl and subsequent oxidation with dimethyldioxirane afforded the enones 126 and 127. This result shows a regiodivergent KR of racemic ketone 122. 

A new convenient polymer modification for the conversion of the Si—H to Si—OH by the selective oxidation of the Si—H bond by dimethyldioxirane has been described. The oxyfunctionalization of the silane precursor polymers proceeded rapidly and quantitatively and can be applied to the synthesis of a wide variety of novel silanol polymers with specific properties from the corresponding precursor polymers containing Si—H functional groups. Control over the properties of these silanol polymers, such as reactivity and self-association of silanols, was realized through the placement of different substitute groups bonded directly to the silicon atom and by the variation of silanol composition in a copolymer. These novel silanol polymers with a... 

Finally, dimethyldioxirane is a convenient oxidant for converting silanes into their silanols by Si —H insertion. When optically active trialkylsilanes are used, the Si — H insertion proceed with complete retention of configuration [38]. The advantage of this highly selective method of hydroxylating silanes is the fact that under the strictly neutral conditions no siloxanes are produced. Likewise,... 

As previously demonstrated, dimethyldioxirane is a mild and selective oxidizing reagent for the conversion of Si-H-functionalized organo- or metallo-silanes to the corresponding silanols [3b, 6]. This method was applied to generate the ferriomethyl-substituted silanols, silanediols and silanetriols 4a-c from 3a-c in acetone at -78°C (Scheme 1, route a). Additionally, 4a,b were prepared by hydrolysis of the ferriomethylchlorosilanes 5a,b in diethyl ether at 0°C in the presence of the auxiliary base EtsN (Scheme 1, route b). 

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