6533b7d8fe1ef96bd126ac7d

RESEARCH PRODUCT

Zirconium, hafnium and yttrium complexes containing two linked amido— tetramethylcyclopentadienyl ligands: Synthesis, reactivity and molecular structure of Hf(η5:η1−C5Me4SiMe2NiPr)2

subject

description

Abstract Zirconium and hafnium complexes M(η5: η1−C5Me4SiMe2NR′)xCl(4−2x) (M = Zr, Hf; x = 1, 2; R′ = iPr, tBu) containing one or two linked amido-tetramethylcyclopentadienyl ligands C5Me4SiMe2NR′ have been synthesized by the reaction of the dilithium derivative Li2(C5Me4SiMe2NR′) with MCl4(THF)2. The crystal structure of the hafnium complex Hf(η5: η1−C5Me4SiMe2NiPr)2 has been determined by a single-crystal X-ray diffraction study and shows a C2-symmetric helical metallocene, in which the amido ligands are bonded as π-donor ligands with Hf—N bond lengths of 2.115(2) A. The isoelectronic heterobimetallic yttrium complex Li[Y(η5: η1−C5Me4SiMe2NCH2CH2OMe)2] reacts with phenylacetylene to give the bis(phenylacetylide) derivative Li[Y{η5−C5Me4SiMe2NH(CH2OMe)}2(CCPh)2].