Chapter 2
Circularly Polarized Luminescence
of Axially Chiral Binaphthyl Fluorophores
Yoshitane Imai
Abstract Axially chiral fluorophores bearing a variety of functionalities have
been successfully developed using chiral binaphthyl units. These axially chiral
binaphthyl fluorophores emit circularly polarized luminescence (CPL) in their
solution-dissolved states, organic polymer-film-dispersed states, and inorganic
pellet-dispersed states. The CPL emitted from an axially chiral binaphthyl
fluorophore is easily tuned by (1) adjusting the dihedral angle in the binaphthyl
unit, (2) employing the neighboring group effect between binaphthyl units, and
(3) controlling their external environments, without the need for the enantiomeric
compound.
2.1 Introduction
Organic compounds with chiroptical properties are very important for the development of new functional organic materials.
Axially chiral binaphthyl is a significant fundamental chiral unit that is used to
introduce chirality into molecules and materials. An axially chiral binaphthyl
organic fluorophore that can emit circularly polarized luminescence (CPL) is
therefore very useful, since the binaphthyl unit exhibits both chirality and fluorescence [1–20].
In this chapter, the solution- and solid-state CPL properties of various axially
chiral binaphthyl fluorophores are introduced.
Y. Imai (*)
Kindai University, Osaka, Japan
e-mail: y-imai@apch.kindai.ac.jp
© Springer Nature Singapore Pte Ltd. 2020
T. Mori (ed.), Circularly Polarized Luminescence of Isolated Small Organic
Molecules, https://doi.org/10.1007/978-981-15-2309-0_2
11
Circularly Polarized Luminescence
of Axially Chiral Binaphthyl Fluorophores
Yoshitane Imai
Abstract Axially chiral fluorophores bearing a variety of functionalities have
been successfully developed using chiral binaphthyl units. These axially chiral
binaphthyl fluorophores emit circularly polarized luminescence (CPL) in their
solution-dissolved states, organic polymer-film-dispersed states, and inorganic
pellet-dispersed states. The CPL emitted from an axially chiral binaphthyl
fluorophore is easily tuned by (1) adjusting the dihedral angle in the binaphthyl
unit, (2) employing the neighboring group effect between binaphthyl units, and
(3) controlling their external environments, without the need for the enantiomeric
compound.
2.1 Introduction
Organic compounds with chiroptical properties are very important for the development of new functional organic materials.
Axially chiral binaphthyl is a significant fundamental chiral unit that is used to
introduce chirality into molecules and materials. An axially chiral binaphthyl
organic fluorophore that can emit circularly polarized luminescence (CPL) is
therefore very useful, since the binaphthyl unit exhibits both chirality and fluorescence [1–20].
In this chapter, the solution- and solid-state CPL properties of various axially
chiral binaphthyl fluorophores are introduced.
Y. Imai (*)
Kindai University, Osaka, Japan
e-mail: y-imai@apch.kindai.ac.jp
© Springer Nature Singapore Pte Ltd. 2020
T. Mori (ed.), Circularly Polarized Luminescence of Isolated Small Organic
Molecules, https://doi.org/10.1007/978-981-15-2309-0_2
11