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Palladium acetate [Pd(OAc)(2)]-catalyzed Hiyama cross-coupling of arenediazonium salts with organosilanes was found to generate biaryl products in high yields in alcoholic solutions. The simple and efficient protocol does not require any bases, ligands, or air/moisture. The transformation can tolerate either electron-donating or electron-withdrawing functional groups. Theoretical studies show that the transmetalation is the rate-limiting step for the cross-coupling reaction and both acetate and tetrafluoroborate anions may be involved in the direct reaction with the silicon atom.

Figure 5. a) Normalized PL spectra of MPCbZ during the hand-actuated grinding process. b) Powder X-ray diffraction (PXRD) patterns and time-resolved spectra c) of Re-phase in the pristine state and after slight and full grinding. d) The absorption spectra of MPCbZ in the Rephase and full-grinding state.

This article discusses the role of covariance correlation tensor in the establishment of the criterion of quantum entanglement. It gives a simple example to show the powerfulness in the treatment of quantum dense coding , and illustrates the fact that this method also provides theoretical basis for establishing corresponding knotted pictures.

For piezo-, vapo-, and thermochromic materials, it remains a challenge to figure out underlying reason for fluorescence color changes upon external stimulation and determine why only some fluorophores reveal emission switching. A novel triphenylacrylonitrile derivative (TPAN-MeO) with remarkably twisted 10 conformations has been carefully prepared via the Suzuki coupling reaction. The fluorescence of TPAN-MeO in aggregate state depends on the polymorphism forms: three crystalline forms BCrys, SCrys and YCrys are brightly blue, sky-blue and yellow emission, respectively; meanwhile the amorphous powders are also strong fluorescent with green emission. The crystals BCrys and SCrys indicate the mechano-and piezochromism in that grinding and high pressure could alter emission colour, respectively. In addition, 15 the amorphous film reveals vapo-and thermochromic behaviour in that organic vapour and heating could change the green colour into sky-blue. Interestingly, the solvent vapour and heating stimuli can trigger a crystal-to-crystal transformation between SCrys form and YCrys form.

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