Tuning the Polarity of HierarchicallyAssembled Helicates

Catechol ligands bearing ester groups in 3-position ( 1A, B, 2) are building blocks for the formationof triply lithium-bridged dinuclear helicate-type complexes [Li 3 ( 1A, B, 2) 6 Ti 2 ] - .Attachment of appropriate functionalities at the ester unit allowsthe fine tuning of the polarity of the compounds to afford solubilityin highly nonpolar as well as highly polar solvents. The investigations showthat the internal dinuclear core is stable in a broad variety of solvents,even in water.