Arenes silylations, triethylsilane

The first example of silylation of C-H bonds in arenes with hydrosilanes was reported by Curtis [2]. Later, silylation of C-H bonds with triethylsilane using a rhodium catalyst was reported (Scheme 3) [3, 4], The reaction of arenes with bis(hydrosilane) using a platinum catalyst involves a bis(silyl)platinum species in the coupling reaction (Scheme 3) [5]. In these non-chelation-assisted reactions possible regioisomers should be formed. 

A very attractive method for the dehydrogenative silylation of arenes via the C-H bond cleavage has been recently reported by Kakiuchi et al. [15]. The reaction of aryloxazolines with trialkylsilanes (mostly triethylsilane) catalyzed by Ru complexes results in the formation of ortho-silylated aryloxazolines in good-to-excellent yields (Eq. 7). 

A similar silylation reaction of benzene with triethylsilane also took place under photoirradiation conditions [88]. Lower catalyst loading improves the selectivity of the corresponding silylbenzene (Eq. 43). This catalyst system can also be applied to the dehydrogenative silylation of arene with hexaorganodis-ilane. 

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