Merck

Ansa-bridged bis(benzene) titanium complexes.

Chemistry (Weinheim an der Bergstrasse, Germany) (2015-06-26)
Holger Braunschweig, Charlotte Brückner, Mehmet Ali Celik, Klaus Dück, Florian Hupp, Thomas Kramer, Johannes Krebs, Ivo Krummenacher
ABSTRACT

Taking advantage of an improved synthesis of [Ti(η(6) -C6 H6 )2 ], we report here the first examples of ansa-bridged bis(benzene) titanium complexes. Deprotonation of [Ti(η(6) -C6 H6 )2 ] with nBuLi in the presence of N,N,N',N'',N''-pentamethyldiethylenetriamine (pmdta) leads to the corresponding 1,1'-dilithio salt [Ti(η(6) -C6 H5 Li)2 ]⋅pmdta that enables the preparation of the first one- and two-atom-bridged complexes by simple salt metathesis. The ansa complexes were fully characterized (NMR spectroscopy, UV/Vis spectroscopy, elemental analysis, and X-ray crystallography) and further studied electrochemically and computationally. Moreover, [Ti(η(6) -C6 H6 )2 ] is found to react with the Lewis base 1,3-dimethylimidazole-2-ylidene (IMe) to give the bent sandwich complex [Ti(η(6) -C6 H6 )2 (IMe)].

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
n-Butyllithium solution, 2.7 M in heptane
Sigma-Aldrich
n-Butyllithium solution, 2.5 M in hexanes
Sigma-Aldrich
n-Butyllithium solution, 2.0 M in cyclohexane
Sigma-Aldrich
N,N,N′,N′′,N′′-Pentamethyldiethylenetriamine, 99%
Sigma-Aldrich
n-Butyllithium solution, 1.6 M in hexanes
Sigma-Aldrich
n-Butyllithium solution, 11.0 M in hexanes
Sigma-Aldrich
n-Butyllithium solution, 1.4 M in toluene