Reaction environment and ligand lability in group 4 Cp2MXY (X, Y = Cl, OtBu) complexes.
Despite their usefulness in catalytic and materials chemistry, the mixed cyclopentadienyl/alkoxide complexes of Ti, Zr, and Hf (Cp2M(OR)2) have few reliable synthetic routes available to them. We describe the use of mechanical ball milling to promote halide metathesis from Cp2MCl2, and compare these results to those obtained in hexanes and THF. Even without solvent, ring lability is extensive with titanium complexes, and alkoxide compounds with 0-3 Cp rings are isolated. The ball milling reactions are much faster than those in solution, but the distributions of products are similar to those obtained in hexanes, although different from those in THF. The range of compounds obtained from Zr and Hf starting materials is more limited, as Cp ring exchange does not occur.
Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, USA. t.hanusa@vanderbilt.edu.
Nicholas C
NC
Boyde
Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, USA. t.hanusa@vanderbilt.edu.
Nicholas R
NR
Rightmire
Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, USA. t.hanusa@vanderbilt.edu.
Eric J
EJ
Bierschenk
Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, USA. t.hanusa@vanderbilt.edu.
Grant W
GW
Steelman
Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, USA. t.hanusa@vanderbilt.edu.
Timothy P
http://orcid.org/0000-0002-7935-5968
TP
Hanusa
Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
William W
WW
Brennessel