Different types of LB films of a 7-aminocoumarin derivative bearing a rigidified amino group were prepared and investigated. Absorption spectra showed a shift to the blue range which increased when a monolayer was changed through z-and x-type multilayers to a y-type multilayer structure. Depending on the type of the films, both the absorption and the emission bands were in fresh samples evidently made up of several aggregate components with different relative portions. The differences decreased with both time and UV irradiation and the absorption bands shifted to the blue and the emission bands to the red, showing an increasing portion of H aggregates in all film types. Finally a large Stokes shift was observed, 166 nm in a y-type structure. Polarized absorption and fluorescence measurements showed that the absorption transition moments of the coumarin chromophore were oriented parallel to each other and an angle between the absorption and emission transient moments was about 63°.

Preparation of 2,2‐disubstituted and 2‐monosubstituted alkenylboronic acid esters from aliphatic and aromatic ketones and aldehydes by the boron‐Wittig olefination with bis[(pinacolato)boryl]methane was examined and applied on the multigram scale. The influence of the substrate steric and electronic features on the overall efficiency and stereochemical outcome of the reaction was studied. Additionally, a series of diversely functionalized (hetera)cycloalkylidenemethyl and (hetera)cycloalkyl boronic acid‐derived building blocks was synthesized.

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