Binaphthyl–Bipyridyl Cyclic Dyads as a Chiroptical Switch
摘要:
A series of chiral cyclic dyads, axially chiral binaphthyls linked to a 3,3'-bipyridyl, was synthesized. The dyad 2 bearing methoxy groups exhibited ON/OFF properties in circularly polarized luminescence (CPL), yielding a vertical bar g(lum)vertical bar of 1.6 X 10(-3) or 0 without any change in fluorescence. This type of CPL switch is unprecedented. Regioisomer 4 exhibited a dextro/levo rotation switching ability in [alpha](D). X-ray structures as well as experimental and theoretical analyses suggested that the switching properties depended on conformational changes.
Visible Light-Driven, Gold(I)-Catalyzed Preparation of Symmetrical (Hetero)biaryls by Homocoupling of Arylazo Sulfones
作者:Lorenzo Di Terlizzi、Simone Scaringi、Carlotta Raviola、Riccardo Pedrazzani、Marco Bandini、Maurizio Fagnoni、Stefano Protti
DOI:10.1021/acs.joc.2c00225
日期:2022.4.1
The preparation of symmetrical (hetero)biaryls via arylazo sulfones has been successfully carried out upon visiblelight irradiation in the presence of PPh3AuCl as the catalyst. The present protocol led to the efficient synthesis of a wide range of target compounds in an organic-aqueous solvent under photocatalyst-free conditions.