Action d'organometalliques sur des dialcoxysilanes cycliques et acycliques

The reaction of various organometallics with cyclic and acyclic dialkoxysilanes has been studied.In the case of the acyclic compounds, phenyl-α-naphthylmethoxyborneoxy- and phenyl-α-naphthylmethoxycyclohexyloxy-silane, our results confirm those previously observed with phenyl-α-naphthylmethoxymethoxysilane. The reactions are selective. In ether, aromatic and saturated organomagnesium compounds substitute only the methoxy group with retention, but allylic and benzylic organomagnesium substitute the bulky alkoxy group with inversion.In THF and DME, irrespective of the type of organomagnesium compound, the methoxy group alone is substituted with retention of configuration.With the cyclic compounds, 2-methoxy-2-silaindane, both methoxy and menthoxy groups are substituted and our results confirm the tendency of cyclic derivatives to be substituted with retention of configuration.