Chirality switching is intriguing for the dynamic control of the electronic and optical properties in nanoscale materials. The ability to photochemically switch the chirality in liquid crystals (LCs) is especially attractive given their potential applications in electro-optic displays, optical data storage, and the asymmetric synthesis of organic molecules and polymers. Here, we present a dynamic photoswitching of the helical inversion in chiral nematic LCs (N*-LCs) that contain photoresponsive axially chiral dopants. Novel photoresponsive chiral dithienylethene derivatives bearing two axially chiral binaphthyl moieties are synthesized. The dihedral angle of the binaphthyl rings changes via the photoisomerization between the open and closed forms of the dithienylethene moiety. The N*-LCs induced by the dithienylethene derivatives that are used as chiral dopants exhibit reversible photoswitching behaviors, including a helical inversion in the N*-LC and a phase transition between the N*-LC and the nematic LC. The present compounds are the first chiral dopants that induce a helical inversion in N*-LC via the photoisomerization between open and closed forms of the dithienylethene moiety.
AIE active triphenylamine–HBT chromophores were synthesized via Suzuki coupling reaction and their emission properties due to ESIPT or ICT phenomena were investigated.
Novel, triphenylamino benzothiazole-based excited-state intramolecular protont ransfer (ESIPT) and non-ESIPT fluorophores were prepared by Suzuki coupling reactions. Their photophysical properties in solution,a queous suspension,a nd in the solids tate were systematically investigated. High fluorescenceq uantum efficiencies (F sol % 95 %; F solid % 88 %), moderate Stokes shifts ( % 8000 cm À1 ), microenvironment-sensitive and molecular-framework-dependent emission are the striking features of the protocol described here. Solid-state emission was modulated and interpreteda s ac rossover effect of p-p interactions using single-crystal Xray analyses. The nonplanar/twisted framework of the system helps to avoid noncovalenti nteractions, facilitating the suppression of fluorescenceq uenching in the solid state with high quantum efficiency over 88 %.[a] Dr.Supporting information and the ORCID identification number(s) for the author(s) of this article can be found under http://dx.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.