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Mono-and di-boranil-substituted helicenes were prepared by BF 2 -borylation of the corresponding anils, readily synthesized by condensation of 2-amino-and 2,15-diaminohelicenes with 4-(diethylamino)salicylaldehyde. After enantio-meric resolution using HPLC, their chiroptical properties including circularly polarized fluorescence in solution and in PMMA films were investigated and rationalized with the help of NMR, X-ray and quantum-chemical calculations.

A K+‐sensitive capacitive electrolyte‐membrane‐insulator‐semiconductor (EMIS) based on a novel dibromoaza[7]helicene ionophore has been developed. An ion‐sensitive membrane based on polyvinylchloride (PVC) doped with the ionophore was deposited on the Si3N4/SiO2/Si‐p/Cu‐Al transducer. The properties of the K+‐EMIS chemical sensor were investigated by electrochemical impedance spectroscopy (EIS). All the developed devices upon being tested have shown good sensitivity and linearity responses within the range 10−6 M to 10−1 M of potassium activity, with good selectivity over a wide variety of other cations (Na+, Li+, Cu2+, Ca2+, and Mg2+). To our knowledge, this is the first time that a capacitive field‐effect sensor has been fabricated using helicene as a carrier for K+‐detection, combined with the structure: Si3N4/SiO2/Si‐p/Cu‐Al as a transducer.

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The preparation of new thienyl‐, oxazolyl‐, and pyridyl‐fused benzo[c]fluorenones has been developed from a unique and easily available common precursor. Starting from bromotetralone, a short sequence allowed the construction of various heterocycles followed by Suzuki coupling and final acid‐promoted formation of the central cyclopentanone unit. The flexible strategy allowed the selective preparation of fused penta‐ to hepta‐cyclic architectures. Fully aromatic targets have been obtained through the application of an oxidation process. The influence of structural modulations on the photophysical properties are described.

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