PCP Complexes of Titanium in the +3 and +4 Oxidation State

Abstract

Ti(IV) and Ti(III) complexes using the tBuPCP ligand have been synthesised (tBuPCP = C6H3-2,6-(CH2PtBu2)2). The [tBuPCP]Li synthon can be reacted with TiCl4(THF)2 to form (tBuPCP)TiCl3 (1) in limited yields due to significant reduction of the titanium synthon. The Ti(III) complex (tBuPCP)TiCl2 (2) has been further characterised. This can have half an equivalent of halide abstracted to form [{(tBuPCP)TiCl}2{μ-Cl}][B(C6F5)4] (3) and can also be methylated forming (tBuPCP)TiMe2 (4). All the Ti(III) complexes have been characterised using EPR and x-ray crystallography, giving insight into their electronic structure, which is further supported by DFT calculations.