Organosilicon compounds bond cleavage

Cleavage of the Si-C bond has gained tremendous importance in organic synthesis because of the diversity of the reactions in which organosilicon compounds can be engaged and the very mild conditions of these reactions.319 In some instances, total or partial desilylation is observed as a side or unexpected reaction. For instance, attempted cuprous ion-catalyzed insertion of trimethylsilylmethylisocyanide into the O-H bond of alcohols fails and desilylation occurs whereas insertion in the N-H bond of amines takes place in high yield (see Section IV.D.l.a).292... 

Replacements of one or two chlorine atoms and hydrogen by fluorine were observed in various organosilicon compounds in reactions with xenon difluoride99,135, while aryl-silicon bond cleavage was observed in the presence of potassium fluoride136,137 (Scheme 57). 

More recently, the scope of the reaction has been extended and further mechanistic aspects have been discussed (ref. 37). Cleavage of C-Si bonds of organosilicon compounds is continually receiving much attention in view of its versatile utility in organic synthesis. With functional silicon compounds such as fluoro-, chloro-, alkoxy-, and aminosilanes, the oxidative cleavage of C-Si bonds, giving corresponding alcohols (ref. 38) (Scheme 16), is of special interest for the... 

Thus most of the photochemistry of simple organosilicon compounds appears to involve radical cleavage to form silyl and carbon radicals. The role of radicals in silicon chemistry has been reviewed12,18. However, as will be seen below, when silicon-silicon bonds are present, a much richer and more complex chemistry is observed, since they are much more susceptible to cleavage by processes which lead to other reactive species in addition to silyl radicals. 

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