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• BINOL-based chiral organic emitters have been synthesized. • The molecules with benzoxazole moieties display aggregation induced emission properties. • The molecules with quinazolinone moieties exhibit acidochromic properties. • Compound 5 has specific aggregation-induced circular dichroism enhancement property. The development of chiral organic fluorescent molecules has attracted broad attention for their various optical applications. In this work, four pairs of chiral fluorescent molecules based on binaphthanol structure have been designed and synthesized. These molecules show blue fluorescent emission in organic solvents with good fluorescent quantum yields and large Stokes shifts. The molecules with benzoxazole moiety display aggregation-induced emission effect in methanol/water solutions, while molecules with quinazolinone moiety show aggregation-caused quenching properties. Moreover, compounds with quinazolinone moiety exhibit acidochromic properties in aqueous solution with different pH values, and their emission intensity are significantly enhanced in strongly acidic conditions. The chiral molecules generally have good circular dichroism intensity. Their R- and S- enantiomers show mirror-imaged circular dichroism curves. Further studies reveal that compound with mono quinazolinone moiety has specific aggregation-induced circular dichroism enhancement properties. This work provides a new strategy for obtaining chiral BINOL-based fluorescent molecules with unique optical properties. BINOL-based chiral organic emitters with benzoxazole or quinazolinone moieties have been synthesized. These molecules exhibit aggregation induced emission, acidochromic and chiral optical properties. [Display omitted] [ABSTRACT FROM AUTHOR]

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]