The synthesis, characterization, and photophysical properties of a series of supramolecular triads consisting of a tin(IV) porphyrin with axial ligands of ortho‐, meta‐, and para‐hydroxyphenyl naphthalenediimides are presented. For the meta‐ and para‐hydroxyphenyl derivatives, efficient and solvent‐viscosity‐dependent quenching of porphyrin fluorescence is observed. Experimental and theoretical studies demonstrate that, in these compounds, photoinduced electron transfer from the phenolate to the porphyrin is modulated by large amplitude rotational motions of the naphthalenediimide. These compounds are novel examples of fluorescent molecular rotors, and their potential use as environmental probes of local viscosity and temperature are discussed.

SummaryTwo approaches, based on imino-aldol additions, to the asymmetric synthesis of cyclic /~-amino acids are reported. In each case a chiral auxiliary was employed attached either to the enolate or to the imine. The relative efficacy of these two synthetic methods is also briefly compared with the former still the preferred route as the latter is currently limited to the preparation of N-sulfonyl fl-amino acids.

Inspired by nature and its ability to form well‐defined architectures on the nanoscale, this chapter investigates not only examples of hybrid nanostructured materials that utilize the building blocks of nature, such as DNA, biopolymers, and bilayers, but also of biomimicry.

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