om5b00303_si_001.pdf (1.34 MB)
Synthesis of Titanium Complexes Containing an Amine Triphenolate Ligand of the Type [TiX{(O-2,4‑R2C6H2)‑6-CH2}3N] and the Ti–Al Heterobimetallic Complexes with AlMe3: Effect of a Terminal Donor Ligand in Ethylene Polymerization
journal contribution
posted on 2015-07-13, 00:00 authored by Kotohiro Nomura, Udomchai Tewasekson, Yuki TakiiThe synthesis of various titanatranes
containing tris(aryloxo)amine
ligands, TiX[{(O-2,4-R2C6H2)-6-CH2}3N] [R = Me (1), tBu (2); X = OiPr (a), OtBu (b), OCH(CF3)2 (c), OC(CF3)3 (d), Cl (e)], and some reactions with
Al alkyls have been explored. The Ti–Al heterobimetallic complexes
[TiMe{(O-2,4-Me2C6H2-6-CH2)2(μ2-O-2,4-Me2-C6H2-6-CH2)}N]-[Me2Al(μ2-OR′)] [R′ = tBu
(3b), CH(CF3)2 (3c), C(CF3)3 (3d)] were isolated
by reaction of 1b–d with 1 equiv
of AlMe3, whereas reaction of 2b with AlMe3 in toluene did not take place under the same conditions,
and the reaction of 2c afforded the methyl complex TiMe[{(O-2,4-tBu2C6H2)-6-CH2}3N]. Structures of 3b,c were determined by X-ray crystallography. These complexes exhibited
high catalytic activities for ethylene polymerization in n-octane in the presence of MAO, and the activity by 1 and 2 was affected by the terminal donor ligand (X)
as well as the substituent on the atrane ligand (R). The activities
by 1c,d increased upon addition of AlMe3, and the corresponding heterobimetallic complexes (3c,d) showed high activities, whereas an increase
in the activity upon addition of AlMe3 was not observed
by 1b,e, and 2c,e.