Spiro- und monocyclische Zirkonium(IV)-amide Zr(L2)2 und L2ZrCl2 mit L2 = ( ? NMe ? SiMe2)2 Y (Y = NMe,O, CH2)

Spiro and Monocyclic Zr(IV) Amides Zr(L₂)₂ and L₂ZrCl₂ with L₂ = (? NMe? SiMe₂)₂ Y (Y = NMe, O, CH₂) The preparation of the spirocyclic Zr(IV) amides Zr[(NMeSiMe₂)₂Y]₂, Y = NMe, O, CH₂, by the reaction of ZrCl₄ with α, ω-dilithio diamines is reported. The monomeric spiranes are cleaved by ZrCl₄ to yield the monocyclic compounds Y(SiMe₂NMe)₂ZrCl₂. These are oligomeric or polymeric; the i.r. spectra suggest a structure consisting of edge-sharing [L₂ZrCl_4/2] octahedra.