SYNTHESIS,CHARACTERIZATION, AND REACTIONS OF MONOMERIC TITANIUM COMPLEXES CONTAINING A CHELATING BIS(PHENOLATE) LIGAND [1, 2]

Abstract

The synthesis of Ti(iso)Cl₂ (iso = the dianion of 2, 2′-ethylidenebis(4, 6-di-rert-butylphenol)) is described. Metathesis reactions of this complex with Grignard reagents, as well as alkali metal salts, yielded Ti(iso)X₂ (X = CH₃, CH, Ph, CH₂SiMe₃, OCMe₃, or NMe₂). Reactions of the Ti-C bond in Ti(iso)(CH₃)₂ toward halogens, active hydrogen compounds, and acetone were studied. In addition. Ti(iso)(X)(Y) (X = CI or CH₃; Y = OC₆H₂-2, 6-^tBu₂-4-Me) could be prepared with the formation of only one coordination isomer. The new complexes have been thoroughly characterized by ¹H and ¹³C NMR spectroscopies. The solid state structure of Ti(iso)Cl₂ was determined via single crystal X-ray diffraction methods. The complex is monomeric, with approximately tetrahedral geometry about the titanium ion. The structure of Ti(iso)Cl₂ is compared to that of Ti(ultra)Cl₂ (ultra = the dianion of 2, 2′-mefhylenebis(6-tert-butyl-4-mefhylphenol)), which was redetermined to greater precision.