Zirconium and hafnium mono(alkyl) complexes containing a tridentate linked amido-tetramethylcyclopentadienyl ligand. Molecular structure of Hf( η5: η1: η1-C 5Me 4SiMe 2NCH 2CH 2OCH 3)Cl 2

Abstract

Zirconium and hafnium complexes M( η 5: η 1: η 1-C 5Me 4SiMe 2NCH 2CH 2OMe)Cl 2 (M=Zr, Hf) containing the tridentate 2-methoxyethylamido-functionalized tetramethylcyclopentadienyl ligand C 5Me 4SiMe 2NCH 2CH 2OMe have been synthesized by the reaction of the dilithium derivative Li 2[C 5Me 4SiMe 2NCH 2CH 2OMe] with MCl 4(THF) 2. Selective monoalkylation of the dichloro complexes gave complexes of the type M( η 5: η 1: η 1-C 5Me 4SiMe 2NCH 2CH 2OMe)(R)Cl (R=CH 2Ph, o-C 6H 4CH 2NMe 2). The crystal structure of the hafnium dichloro complex Hf( η 5: η 1: η 1-C 5Me 4SiMe 2NCH 2CH 2OMe)Cl 2 has been determined by X-ray crystal diffraction and shows a trigonal bipyramidal structure in which the five-membered ring and the methoxy function adopt the apical positions. Crystal data: monoclininc P2 1/ c, a=12.069(2) Å, b=15.362(3) Å, c=9.949(2) Å, β=92.04(1)°, V=1843.4(6) Å 3, Z=4, R=0.0471, R w=0.0952.