New straightforward route for the synthesis of some 1‐oxa‐2‐silacyclopentane derivatives

Tris(dimethylsilyl)methyl lithium, (HSiMe₂)₃CLi, reacts with allyl, phenyl, benzyl, n‐propyl and n‐butyl glycidyl ethers in THF at ‐5 °C to give 1‐oxa‐2‐silacyclopentane derivatives. It seems that ring closure is facilitated by conversion of the Si? H bond into an Si? O bond. Glycidyl methacrylate (GM) random copolymers with 4‐methyl‐ and 4‐methoxy styrene, synthesized by solution free radical polymerization at 70 (±1) °C with α,α‐azobis(isobutyronitrile) (AIBN) as initiator, contained pendant epoxide functions. Treatment of these with (HSiMe₂)₃CLi did not lead to intramolecular nucleophilic attack as found for simple epoxides.