Facile α-C–H activation in 14-electron zirconium half-sandwich compounds: evidence for a new catalyst deactivation pathway

Abstract

The electron-deficient zirconium diene complex [Zr(Cp″)Me(C 4 H 4 Me 2 -2,3)] [Cp″ = C 5 H 3 (SiMe 3 ) 2 -1,3] cleanly eliminates methane to give an unusual dinuclear dienyl complex [Zr(Cp″)(µ-η 1 :η 4 -C 4 H 3 Me 2 -2,3)] 2 , characterised by a new type of µ-η 1 :η 4 -butadienyl coordination mode; the complex and its zwitterionic reaction product with B(C 6 F 5 ) 3 provide support for catalyst deactivation processes involving alkane elimination reactions.