ChemInform Abstract: Dimesitylsilyl Derivatives of Zirconium.

ChemInform Abstract

The silyl-Li compound (IV) prepared as shown reacts with the halomethylzirconocenes (V) to give the silyl derivatives (VI). While (VIa) is thermally unstable, (VIb) is stable for prolonged periods at room temperature. Treatment of (VIb) with HCl results in the formation of methane and the chlorosilyl analogue. CO (VII) inserts cleanly into the Zr-C bond of (VIa) giving the acetyl complex (VIII), whereas preferential CO insertion in the Zr-Si bond of (VIb) leads to the unstable silaacyl complex (X) which isomerizes to the enolate hydride (IX). Reaction of (VIb) with AgOSO₂CF₃ results in oxidative cleavage of the Zr-Si bond. Reaction of the zirconocene dichloride (XI) with (IV) does not give a bis(silyl) complex but instead results in dehydrohalogenation to the silane (XIII) and the metallacycle (XII).