In their Communication on page 14282 ff., S. Hecht et al. report on a strategy to improve the switching performance of diarylethene (DAE) photochromes. By introducing bulky substituents in the bridge moiety of dithienylcyclopentenes, derivatives exhibiting enhanced photocyclization quantum yield were obtained, the quantum yield being independent of the environment (solvent). The improved switching efficiency was achieved without compromising on the differences in the optical and redox properties of the ring-open and ring-closed states, thus rendering the new photoswitches ideal candidates for applications in light-gated optoelectronic devices.
Up to three borolyl groups have been installed on a benzene ring, yielding bis- and trisboroles. The adduct formation of these oligoboroles with a variety of pyridine bases is described. In addition, the interplay of the highly Lewis acidic moieties in the meta- and para-substituted bisboroles is addressed by base-transfer reactions. For more details, see Full Paper by H. Braunschweig et al. on page 14292 ff.
In their Full Paper on page 14413 ff., L. M. Rendina et al. report on the first comprehensive calorimetric study of the supramolecular interactions between closo-carborane compounds and β-cyclodextrin (β-CD), and provide fascinating insights into the structural features influencing the thermodynamics of this phenomenon. The nature of the carborane cage itself and the chirality and nature of the substituents on the cage each contribute to its molecular recognition by β-CD.