Dinuclear titanium complexes of thiacalix[4]arene

The reaction of [TiCl4(THF)(2)] with thiacalix[4]arene (H(4)TCA) affords almost insoluble [TCA{TiCl2(THF)}(2)] (1). Single crystal X-ray analysis reveals that the thiacalix[4]arene ligand coordinates at least in a part of the reaction product in an 1,2-alternate cone conformation and that the metal atoms are therefore arranged in opposite directions with respect to a plane through the sulfur atoms of the ligand (anti-configuration). The use of [Ti-2(acac)(4)(mu-O)(2)] as starting material causes the formation of the soluble homodinuclear complex [TCA{Ti(acac)}(2)(mu-O)] (2) in good yields, in which the thiacalix[4]arene ligand adopts a cone conformation and the metal atoms are thus arranged in syn-configuration. Reaction of 2 with 8-hydroxyquinoline leads to substitution of the acetylacetonato ligands of 2 under formation of crystallographically characterized [TCA{Ti(OC9H5N)}(2)(mu-O)] (3).