R. Beckhaus, K. Thiele, Dieter Ströhl
Jun 20, 1989
Citations
0
Influential Citations
36
Citations
Journal
Journal of Organometallic Chemistry
Abstract
Abstract Bis(pentamethylcyclopentadienyl)metal dichlorides, CP*2MCl2 (M = Ti, Zr, Hf), react with vinyllithium in the molar ratio1/2to form the corresponding divinyl compounds Cp*2M(CH=CH2)2. The hafnium compound can be isolated pure. The titanium and zirconium compounds can be detected by low-temperature NMR spectroscopy, but they undergo rearrangements at room temperature. Cp*2Zr-(CH=CH2)2 forms an equilibrium with C p 2 ★ Z r C H = C H C H 2 ︹ C H 2 as the zirconacyclopent-2-ene derivative whereas Cp*2Ti(CH=CH2)2 surprisingly is converted quantitatively into C p 2 ★ T i C ( = C H 2 ) C H 2 ︹ C H 2 which exhibits a titanacyclobutane derivative with an exocyclic methylidene group.