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Cyclic phenylazomethines with methylene spacers (CPA-M) are obtained by dehydration of diamine with diketone. During the titration of CPA-M 4mer with FeCl3, we observe two consecutive isosbestic points in the UV−vis spectra. We conclude that complexation occurs in two consecutive steps. Our analysis suggests that the stepwise metal ion assembly is caused by a difference in the basicity of the imine conformers. Metal ion binding first occurs at the Zimines followed by coordination to the Eimine. Finally, metal ion assembly in this compound can be controlled electrochemically.

We prepared crystals of di-n-alkyl esters of phosphoric acid with chain lengths of n 10, 12, 14, 16, and 18. These were characterized by single-crystal X-ray analysis and differential scanning calorimetry (DSC). It was found that the alkyl chains are in an extended all-trans conformation and aligned close to perpendicular, forming V-shaped molecules. This is in strong contrast to the typical arrangement of the alkyl chains of phospholipids where the two alkyl chains are arranged parallel in the same direction (e.g., tuning fork configuration in bilayers). Additionally, it was found that the arrangement of the V-shaped molecules of the di-n-alkyl esters in neighboring stacks of the lamellar crystals is antiparallel for short chain lengths (n 10 and 12) and parallel for the longer (n 14 and 16). DSC reveals that the melting of the crystals increases systematically with increasing chain lengths from 48 to 82 °C. The contribution of each methylene group to the melting enthalpy (70−133 kJ/mol) is independent of the chain length (3.9 kJ per mol CH2).

Molecular or supramolecular systems capable of electro- and photostimulated color changes are still rare. We present a device design based on an electrostatic complex of a nanoscopic polyoxometalate cluster and a polyelectrolyte. The coating reversibly changes color from transparent to blue by photo- and/or electroinduced stimulation. The choice of the components results in perfect transparency over the entire visible range, a large optical response, reversible operation, and excellent stability.

We present an approach to fabricate very large, soluble, self-contained metallosupramolecular entities employing a template-directed strategy based on charged nanoparticles: consecutive deposition of negatively charged macromolecules and positively charged metallosupramolecular coordination polyelectrolytes is exploited to assemble the metallosupramolecular components on the nanoparticles.