Synthesis, structure and reactivity in styrene polymerization by heterocyclic alkoxy- and thiolatotitanium(IV) complexes

The reaction of [Ti(OiPr)(4)] or [TiCl4(THF)(2)] with two equivalents of pyridyl alcohols or pyridyl or pyrimidinyl thiols has proven to be a good preparative method to obtain a variety of non-metallocene diisopropoxo- or dichlorotitanium(IV) complexes. The complexes [Ti(X)(2){2-(OCH2)-6-R-(C5H3N)}(2)] were found to be dynamic at room temperature, with the heterocyclic alkoxy ligand dissociating and recoordinating in a k(2)-N,O chelate fashion, as revealed by a single-crystal X-ray analysis of [Ti(OiPr)(2){2-(OCH2)(C5H4N)}(2)] (1). The dynamic behavior of some of the resulting thiolato complexes was also studied and the single-crystal X-ray analysis of [Ti(OiPr)(2){2-S-4,6-Me-2-(C4HN2)}(2)] (5) revealed a k(2)-N,S system for these complexes. These complexes show catalytic activity in the polymerization of styrene upon activation with methylaluminoxane. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006).