Synthesis, structural characterization, and theoretical investigation of compounds containing an Al-O-M-O-Al (M=Ti, Zr) core.
We report a facile route to the first molecular compounds with the Al-O-M-O-Al (M=Ti, Zr) structural motif. Synthesis of L(Me)Al(mu-O)M(NMe2)2(mu-O)Al(Me)L [L=CH{N(Ar)(CMe)}2, Ar=2,6-iPr2C6H3; M=Ti (7), Zr (8)] was accomplished by reacting the monometallic hydroxide precursor L(Me)Al(OH) (1) with Ti(NMe2)4 or Zr(NMe2)4 under elimination of Me2NH in good yield. The crystal structural data confirm the trimetallic Al-O-M-O-Al core in both 7 and 8. Preliminary investigation on catalytic activity of these complexes reveals low activity of these complexes in ethylene polymerization as compared to the related oxygen-bridged metallocene-based heterobimetallic complexes L(Me)Al(mu-O)M(Me)Cp2 (M=Ti, Zr) which could be attributed to the relatively lower stability of the supposed cationic intermediate as revealed by DFT calculations.
Institute of Inorganic Chemistry, University of Göttingen, Tammannstrasse 4, 37077 Göttingen, Germany.
Swadhin K
SK
Mandal
Prabhuodeyara M
PM
Gurubasavaraj
Herbert W
HW
Roesky
Rainer B
RB
Oswald
Jörg
J
Magull
Arne
A
Ringe