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Chiral organic fluorescent materials have attracted broad attention for their application in various chiroptical devices. Helicenes possess special helical structure and unique optical properties, and have been utilized to develop chiral organic fluorescent materials with excellent chiroptical performance. However, the low luminescence efficiency of helicene-based chiral fluorescent materials in solid state limits their practical applications. In this work, chiral organic fluorescent emitters with helicene moiety have been developed from binaphthanol structure. These BINOL [4]helicene compounds display aggregation-enhanced emission properties, and have strong blue emission in solid state with fluorescent quantum yield up to 0.67. The DFT calculation reveals that these compounds have highly twisted molecular structures. Thus, the excellent fluorescent properties in solid state could be aroused by the highly contorted molecular structures, which could limit the π-π stacking of adjacent molecules in solid state. The enantiomers of these compounds show strong Cotton effects in circular dichroism spectra, and the molecules with 4-methoxy phenyl moiety exhibit circularly polarized luminescence properties. Highly twisted BINOL- [4]helicene hybrids have been synthesized, which have strong fluorescent emission in solid state and chiral optical properties. [Display omitted] • Chiral binol-[4]helicene hybrids have been synthesized. • These molecules display aggregation-enhanced emission properties. • These molecules show strong fluorescent emission in solid state. • Compound 6 exhibits circularly polarized luminescence property. [ABSTRACT FROM AUTHOR]

The design and exploration of efficient organic fluorophores have attracted significant scientific interest for their various potential applications. As blue fluorescent materials are essential for the achievement of a full-color display and white emission, the development of new efficient organic blue-emitting materials is of great importance. In this work, we found that simple organic molecules 2-aryloxybenzo[d]oxazoles could act as novel organic fluorophores with special AIE properties and efficient blue fluorescent emission in the solid states. Compounds 3 and 4 possess moderately high quantum yields at 10.3% and 11.4%, respectively. The CIE coordinates indicate that most of these compounds are deep-blue emitters. The single crystal structure of compound 3 shows that it has a twisted V-shape molecular structure with J-type aggregation. Noncovalent interactions widely exist in the crystal structures, while π-π stacking interactions are not observed between adjacent aromatic rings. The special fluorescent properties of these new emitters could ascribe to the unique molecular packing mode in the crystal structure. This work provides a new strategy to access organic solid-state fluorophores with deep-blue emission. Simple organic molecules (2-aryloxybenzo[d]oxazoles) act as novel organic fluorophores with special AIE properties and efficient deep blue fluorescent emission in the solid states. Image 1 • 2-Aryloxybenzo[d]oxazoles derivatives are designed and synthesized. • These fluorophores show special AIE properties. • These compounds exhibit efficient deep blue emission in solid states. [ABSTRACT FROM AUTHOR]