Homo- and Heterometallic Aluminum and Titanium Complexes of Tridentate (OSO) Ligand: Synthesis, Structure, and Catalytic Activity
作者:Zofia Janas、Lucjan B. Jerzykiewicz、Piotr Sobota、Krzysztof Szczegot、Dorota Wiœniewska
DOI:10.1021/om050271o
日期:2005.8.1
The tridentate (OSO-functions) biphenol, 2,2'-thiobis4-(1,1,3,3-tetramethylbutyl)phenol} (tbopH(2)), reacts with AlMe3 to give [Al-2(mu-tbop-kappa(3)O,S,O)(2)Me-2] (1). Alcoholysis of 1 results in the formation of [Al-2(mu-OEt)(2)(tbop-kappa(3)O,S,O)(2)] (2). The reaction of 2 with TiCl4 gives the trimeric complex [Ti-3(mu-OEt)(2)(mu-tbop-kappa(3)O,S,O)(2)Cl-6] (3)center dot C6H14. Alkylation of 3 center dot C6H14 with LiMe produces two dimeric complexes, [Ti-2(mu-tbop-kappa(3)O,S,O)(2)Me-4] (4) and [Ti-2(mu-OE)(2)(tbop-kappa(3)O,S,O)(2)Me2] (5)center dot Et2O. Treatment of [Ti-2(mu-OEt)(2)(tbop-kappa(3)O,S,O)(2)(OEt)(2)] with AlMe3 and EtOH afforded the heterobimetallic species, [Ti2Al2(mu-OEt)(6)(mu-tbop-kappa(3)O,S,O)(2)(OEt)(4)] (6). The structures of 1-6 were confirmed by NMR spectroscopy; complexes 1, 3 center dot C6H14, 5 center dot Et2O, and 6 were further investigated by X-ray crystallography. Compounds 3-6, when supported on MgCl2 and activated with aluminum alkyls, effectively polymerize ethene.