The thioester moiety is introduced as a lithium binding unit for the hierarchical formation of titanium(IV) catecholate-based lithium-bridged helicates. In solution, the coordination compounds show a monomer-dimer equilibrium which -in comparison to the oxo esters- is significantly shifted towards the monomers. In addition, the influence of the thioester side chain on the dimerization behavior is investigated and an expansible/compressible molecular switch is synthesized. In the latter case expansion and compression are performed reversibly in methanol, whereas in DMSO spontaneous expansion occurs.
Keywords: helicates; molecular switches; self-assembly; thermodynamics; titanium.
© 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.