Synthesis, Structure and Reactivity in Styrene Polymerization by Heterocyclic Alkoxy‐ and Thiolatotitanium( IV ) Complexes

The reaction of [Ti(O i Pr) 4 ] or [TiCl 4 (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‐(OCH 2 )‐6‐R‐(C 5 H 3 N)} 2 ] were found to be dynamic at room temperature, with the heterocyclic alkoxy ligand dissociating and recoordinating in a κ 2 ‐N,O chelate fashion, as revealed by a single‐crystal X‐ray analysis of [Ti(O i Pr) 2 {2‐(OCH 2 )(C 5 H 4 N)} 2 ] ( 1 ). The dynamic behavior of some of the resulting thiolato complexes was also studied and the single‐crystal X‐ray analysis of [Ti(O i Pr) 2 {2‐S‐4,6‐Me 2 ‐(C 4 HN 2 )} 2 ] ( 5 ) revealed a κ 2 ‐N,S system for these complexes. These complexes show catalytic activity in the polymerization of styrene upon activation with methylaluminoxane. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)