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Efficient catalytic arsa‐Wittig reactions have been developed by using 1‐phenylarsolane as a catalyst. A wide array of aldehydes was converted to the corresponding olefins in high yields with moderate to excellent E stereoselectivity in the presence of a catalytic amount of 1‐phenylarsolane. Moreover, density functional theory calculations were carried out to afford insight into the E/Z selectivity. [ABSTRACT FROM AUTHOR]

Abstract: 2,3,4,5‐Tetraaryl‐1‐phenylarsoles were synthesized by utilizing safely generated diiodophenylarsine and zirconacyclopentadienes. The obtained peraryl arsoles showed aggregation‐induced emission (AIE), where intense emission was observed in the solid states (quantum yields up to 0.61), whereas the corresponding solutions were very weakly emissive. The optical and electronic properties were examined by experimental and computational methods. It was elucidated that the aryl groups at the 2,5‐positions affected the frontier orbitals and the aromaticity of the arsole core. On the other hand, those at the 1,3,5‐positions were perpendicular to the luminophore and effective for a restriction of aggregation‐caused quenching. Because the lone pair of the arsenic atom has a sufficient coordination ability due to the low aromaticity of the arsole moiety, a gold(I) chloride complex of 1,2,3,4,5‐pentaphenylarsole was synthesized. The complex formation caused a blue shift of the emission from the bare ligand. Interestingly, the complex showed luminescent mechanochromism; grinding the crystals with a blue emission (λem=445 nm) gave amorphous samples with a greenish–blue emission (λem=496 nm). [ABSTRACT FROM AUTHOR]