Bis(catecholato-kappa O-2,O ')bis(dimethyl sulfoxide-kappa O)titanium(IV)

Bis(benzene- 1,2- diolato-kappa O-2,O')bis( dimethyl sulfoxide-kappa O)titanium(IV), [Ti(C6H4O2)(2)(C2H6OS)(2)], crystallizes with two crystallographically independent molecules in the space group P2(1)/c emulating orthorhombic Pbca symmetry (beta = 90.0445 (9)degrees]. The two molecules are related by pseudo-glide symmetry, broken by modulation of each one catecholate and dimethyl sulfoxide (DMSO) ligand. Twinning by pseudomerohedry was observed [twin ratio 0.5499 (7):0.4401 (7)]. Complex 3 was obtained by heating of diprotonated titanium tris-catecholate precursor 2(H) in DMSO, by formal displacement of a catechol molecule by two DMSO molecules. Complex 3 is just the second heteroleptic, mono-nuclear, neutral bis-catecholate complex with TiO6 metal coordination, the only other one being its bis-DMF analogue 6. The two molecules of 3 exhibit a distorted octahedral geometry. The geometry and distortions from ideal symmetry of 3 are discussed and compared to 6 and to cationic tris-catecholate titanium complexes.