摘要:
The first series of structurally characterized zirconium complexes that feature both eta(1)- and eta(5)-pyrrolyl coordination modes is reported. Specifically, 2,5-diaryl-pyrrolyl [pyr(Ar2)] ligands (Ar = Ph, 2,4-Xyl) have,been used to prepare [pyr(Ar2)]Zr(NMe2)(3)(NMe2H), [pyr(Ar2)]Zr-(NMe2)(3), [pyr(Ar2)]Zr(NMe2)I-2, and [eta(5)-pyr(Ar2)](2)ZrCl2. DFT calculations indicate that the relative stabilities of the various coordination modes are influenced by both steric factors and the Lewis acidity of the metal center.