443795-75-3Relevant academic research and scientific papers
Pentafulvene complexes of titanium - Synthesis, structure, and fluxional behaviour of Cp′Ti{η6-C5H4=C(p-Tol) 2}Cl (Cp′ = Cp*, Cp)
Stroot,Luetzen,Friedemann,Saak,Beckhaus
, p. 797 - 802 (2008/10/08)
The reaction of Cp′TiCl3 (Cp′ = Cp* or Cp) with magnesium and 6,6-di-para-tolylpentafulvene generates good yields of pentafulvene complexes Cp*Ti{η6-C5H4=C(p-Tol) 2}Cl (4) and CpTi{η6-C5H4=C(p-Tol)2}Cl (5), respectively. The crystal and molecular structure of 4 have been determined from X-ray data and exhibits compared to known η6-pentafulvene complexes an unusual large Ti-C(p-Tol)2 (Fv)-distance (2.535(5) A) evoked by the bulky substituents at the exocyclic carbon. Dynamic 1H-NMR and spin saturation transfer experiments point out a rotation of the fulvene ligand around the Ti-Ct2 axis (Ct2 = centroid of the fulvene ring carbon atoms) with an activation barrier ΔG±C = 60.6 ± 0.5 kJ mol-1 (TC = 314 ± 2 K). For 5 this barrier is significantly larger. Analogous dynamic behaviour is well known for diene complexes, but to our knowledge, it is here first-time described for a pentafulvene complex.
