Solvent-Adaptive Behavior of Oligospirobifluorenes at the Surface of Quartz Crystal Microbalances- A Conformational Process.

Invited for this month's cover are the groups of Siegfried R. Waldvogel at the Johannes Gutenberg University Mainz and of Josef Salbeck at the University Kassel (both Germany). The image shows the swelling of a blowfish to represent the reversible conformational change of an oligospirobifluorene derivative upon solvation.

Solvent-Adaptive Behavior of Oligospirobifluorenes at the Surface of Quartz Crystal Microbalances-A Conformational Process.

Oligospirobifluorenes represent promising building blocks for the generation of microporous sensor materials based on their restricted flexibility. The contact with specific solvents leads to a change of the three-dimensional spirobifluorene structure. The single fluorene moieties unfold to an open structure with an increased volume due to intermolecular interactions with the solvent, detectable by NMR spectroscopy.