Synthesis and structural characterization of a dumbbell-like phenylphosphonate-stabilized Ti-oxide cluster.

In recent years, crystalline polyoxotitanium clusters (PTCs) have attracted increasing attention as a new kind of promising crystalline material. In this work, a PTC stabilized by phenylphosphonate ligands, i.e. hexa-μ-isopropanolato-hexaisopropanolatodi-μ-oxido-hexa-μ-phenylphosphonato-heptatitanium tetrahydrate, [Ti(μ-O)(OP-Phen)(OPr)]·4HO [PTC-54; HOP-Phen is phenylphosphonic acid, CHPO(OH), and HOPr is isopropanol, CHOH], was obtained successfully through a facile one-step solvothermal reaction. The dumbbell-like core structure of PTC-54 can be described as two trinuclear {Ti(μ-O)} building units combined together by six phenylphosphonate ligands and one additional Ti atom, giving rise to a Ti cluster. Adjacent molecules of PTC-54 are further connected through π-π interactions between the phenyl groups to form a supramolecular one-dimensional chain.