Crystal structure of a zwitterionic aza-allyl zirconiumamide complex bearing a Zr+-μ-CH3—B? moiety and one equivalent of n-hexane as a solvent

摘要

The zirconiumamide complex [(cyclo-hex-1-en-yl)cyclo-hexyl-amido]-bis-(di-cyclo-hexyl-amido)[methyl-tris-(penta-fluoro-phen-yl)borato]zirconium(IV) hexane monosolvate, [Zr{N(C 6 H 11 ) 2 } 2 {N(C 6 H 11 )(C 6 H 9 )}{BCH 3 (C 6 F 5 ) 3 }]·C 6 H 14 , is zwitterionic and bears a Zr + — μ -CH 3 —B ? moiety. The reaction of tris-(di-cyclo-hexyl-amido)-methyl-zirconium with the strong Lewis acid tris-(pentafluorophen-yl)borane results in the formation of an aza-allyl zirconium motif by the loss of H 2 in one di-cyclo-hexyl-amido ligand, as shown by single-crystal X-ray diffraction. The Zr IV cation is coordinated to the N atoms of two di-cyclo-hexyl-amido ligands, the π -system of one aza-allyl ligand, and to the μ -CH 3 —B unit, resulting in a distorted tetra-hedral coordination environment. The Zr—N distance to the aza-allyl ligand is elongated, whereas the Zr—C distance to this moiety is found to be shortened in comparison with those to the two Cy 2 N groups (Cy is C 6 H 11 ).