2,6-Bis(methylencyclopentadienyl)-pyridin-zirconocen- und -hafnocendichlorid; Bildung und Kristallstruktur von [C5H3N-2,6-(CH2?C5H4)2Zr(Cl)(OH2)]2[ZrCl6]

2,6-Bis(methylenecyclopentadienyl)-pyridine-zirconocene and -hafnocene Dichloride; Formation and Crystal Structure of [C₅H₃N-2,6-(CH₂? C₅H₄)₂Zr(Cl)(OH₂)[ZrCl₆]] Pyridine bridged metallocene dichlorides of type C₅H₃N-2,6-(CH₂? C₅H₄)₂MCl₂ (M = Zr ( 2 ), Hf ( 5 )) were synthesized. The presence of N → Zr interaction favours the formation of zirconocene cations. Traces of water cause the formation of the salt-like compound [C₅H₃N-2,6-(CH₂? C₅H₄)₂Zr(Cl)(OH₂)]₂[ZrCl₆] 4 from 2 . The new compounds were characterized by ¹H n.m.r., and mass spectroscopy. The X-ray crystal structure of 4 shows discrete cations and anions which are connected by H-bridges.