PREPARATION OF NEW MONOMERIC, OLIGOMERIC, AND POLYMERIC SILYL TRIFLATES

The highly reactive silyl triflates R3SiSO4CF3 are valuable reagents in organosilicon chemistry. New triflate derivatives of mono- and oligosilanes have been prepared by substitution of phenyl groups or hydrogen atoms for the trifluoromethanesulfonyl group. The presence of the electron-withdrawing triflate group leads to a strong deactivation of the other substituents at the silicon atom, and the displacement of a second phenyl group at the same silicon atom is much slower than the first step. For this reason in the case of phenylated oligosilanes stepwise monosubstitution of the silicon atoms has been found. Other new oligomeric silyl triflates are obtained by reaction of silanediyl(triyl) bis(tris)(trifluoromethanesulfonates) with lithium derivatives of organosilicon compounds, Finally, the cleavage of silicon phenyl bonds of poly[methyl(phenyl)silanes] by CF3SO3II leads to triflate derivatives of polysilanes.