Synthesis, structural determination, and ethylene polymerization chemistry of mono(salicylaldiminato) complexes of titanium(IV)

Titanium(IV)mono(salicylaidiminato) complexes [(LTi)-Ti-1(NMe2)(3)] (1) and [(LTiCl3)-Ti-1] (2) have been synthesized by treatment of Ti(NMe2)(4) or TiCl4 with one equivalent of [4,6-Bu'(2)-2-(CH=NBu')C6H3OH] ((LH)-H-1) or [4,6-Bu'(2)-2-(CH-NBu')C6H3OS'Me-3]((LSiMe3)-Si-1) respectively. The compounds are monomeric in solution and in the solid-state. Reactions of TiCl4 with one equivalent of [4,6-Bu'(2)-2-(CH=NCH2Ph)C6H3OH] ((LH)-H-2) and [4,6-Bu'(2)-2-{CH=N(2-C6H4OH)}C6H3OH] ((LH2)-H-3) produced [(LTiCl2)-Ti-2(mu-Cl)](2) (3) and [(LTiCl2)-Ti-3](2) (4), respectively. [(LTiCl2)-Ti-3(THF)] (5) was also produced in quantitative yield when 4 was stirred in THE for 16 h. The reaction of TiCl4 with (LH2)-H-3 (Two equivalents) in toluene gave [(L-3)(2)Ti] (6). The molecular structures of 2-4 and 6 were established by single-crystal X-ray diffraction studies; and 4 displayed a rare face to face pi-pi stacking interaction in its structure. Compounds 1 and 2 showed modest ethylene polymerization activities at 25 degreesC with 900 molar equivalents of methylalumoxane (MAO) as co-catalyst. (C) 2003 Elsevier Science B.V. All rights reserved.