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The use of monophos as a ligand in the palladium‐catalyzed Suzuki diarylation of 2,2′‐diiodo‐1,1′‐binaphthyl under optimized conditions followed a stereoconservative course. However, some chiral P ligands were found to be capable of inducing stereogenic information during this coupling, regardless of the configuration of the starting diiodide. Among those ligands tested in the deracemization approach, binap exhibited the highest level of asymmetric induction, yielding diarylated product in 83 % ee starting from racemic diiodide. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

The Suzuki arylation of enantiopure 2,2'-diiodo-1,1'-binaphthalene affords the 2,2'-diarylated products in considerable yields (up to 52%), however, significantly racemized. The reversed-polarity approach, using novel enantiopure 1,1'-binaphthalene-2,2'-diyldiboronic acid, prepared either by resolution or by stereoconservative boronation, allowed, after optimization of coupling conditions, to obtain the model 2,2'-ditolylated product in good yield (56%) as well, but in addition, without impairing of enantiomeric purity (i.e. stereoconservatively). The developed synthetic approach was found to be an expedient method for the synthesis of enantiopure 2,2'-diaryl-1,1'-binaphthalenes, especially for those with electron-neutral and electron-deficient poor aryl groups. Observing that the diboronic acid decomposes by hydrodeboronation under the reaction conditions, 2-aryl-1,1'-binaphthalenes were isolated as the main products from the reaction with less reactive electron-rich aryl iodides.

The emission properties of three 4-azafluorenone and five new α-carboline fluorophores in both solution and thin solid films were investigated. Fluorescence of the azafluorenone is clearly enhanced in thin solid films due to the presence of phenyl/biphenyl rotors, and these derivatives can be classified as green Aggregation-Induced Emission luminogens (AIEgens) with a non-emissive heteroaromatic core structure. Compared to azafluorenones, emission of α-carbolines is hypsochromically shifted to the blue region of the electromagnetic spectrum, and most of these derivatives exhibit strong violet-blue fluorescence in both solution and thin solid film layers. Further, the effective mobility and electroluminescence of new α-carbolines were investigated in prepared organic field-effect transistors and organic light-emitting diodes, respectively.