was induced since the helical anion complex formed an ion pair with the chiral cation in
the dichloromethane solution. The ion pair of 36ÁCl
–
ÁRR
+ exhibited CPL with a g lum of
1.8 Â 10
À2 in dichloromethane/octane solution (1:1, 1 Â 10
À3 mol L
À1
) at –70
C.
9.6 Summary
An achiral π-conjugated luminophore can exhibit CPL by the chiral arrangement
of the achiral luminophore. The helical supramolecular assembly of an achiral
luminophore is excellent for realizing CPL of the achiral luminophore since the
highly assembled structure in the helical assembly provides good CPL activity.
Furthermore, the supramolecular assembly has an advantage in its stimuliresponsiveness. The development of CPL-active supramolecular assemblies and
their applications are in progress all over the world.
References
1. Bünzli J-CG, Piguet C (2005) Taking advantage of luminescent lanthanide ions. Chem Soc Rev
34:1048–1077
2. Kumar J et al (2015) Circularly polarized luminescence in chiral molecules and supramolecular
assemblies. J Phys Chem Lett 6:3445–3452
3. Sánchez-Carnerero EM et al (2015) Circularly polarized luminescence from simple organic
molecules. Chem Eur J 21:13488–13500
4. Emeis CA, Oosterhoff LJ (1967) Emission of circularly-polarised radiation by optically-active
compounds. Chem Phys Lett 1:129–132
5. Satrijo A et al (2006) Probing a conjugated polymer’s transfer of organization-dependent
properties from solutions to films. J Am Chem Soc 128:9030–9031
6. Wilson JN et al (2002) Chiroptical properties of poly(p-phenyleneethynylene) copolymers in
thin films: large g-values. J Am Chem Soc 124:6830–6831
7. Zhao Y et al (2016) Supramolecular chirality in achiral polyfluorene: chiral gelation, memory of
chirality, and chiral sensing property. Macromolecules 49:3214–3221
8. Dekkers HPJM, Closs LE (1976) The optical activity of low-symmetry ketones in absorption
and emission. J Am Chem Soc 98:2210–2219
9. Schippers PH, Dekkers HPJM (1983) Circular polarization of luminescence as a probe for
intramolecular 1nπà energy transfer in meso-diketones. J Am Chem Soc 105:145–146
10. Schippers PH et al (1983) Circular polarization in the fluorescence of β γ-enones: distortion
in the 1nπà state. J Am Chem Soc 105:84–89
11. Steinberg N et al (1981) Measurement of the optical activity of triplet-singlet transitions.
The circular polarization of phosphorescence of camphorquinone and benzophenone. J Am
Chem Soc 103:1636–1640
12. Phillips KES et al (2001) Synthesis and properties of an aggregating heterocyclic helicene.
J Am Chem Soc 123:11899–11907
13. Field JE et al (2003) Circularly polarized luminescence from bridged triarylamine helicenes.
J Am Chem Soc 125:11808–11809
14. Nakamura K et al (2014) Enantioselective synthesis and enhanced circularly polarized
luminescence of S-shaped double azahelicenes. J Am Chem Soc 136:5555–5558
216
T. Ikeda and T. Haino
the dichloromethane solution. The ion pair of 36ÁCl
–
ÁRR
+ exhibited CPL with a g lum of
1.8 Â 10
À2 in dichloromethane/octane solution (1:1, 1 Â 10
À3 mol L
À1
) at –70
C.
9.6 Summary
An achiral π-conjugated luminophore can exhibit CPL by the chiral arrangement
of the achiral luminophore. The helical supramolecular assembly of an achiral
luminophore is excellent for realizing CPL of the achiral luminophore since the
highly assembled structure in the helical assembly provides good CPL activity.
Furthermore, the supramolecular assembly has an advantage in its stimuliresponsiveness. The development of CPL-active supramolecular assemblies and
their applications are in progress all over the world.
References
1. Bünzli J-CG, Piguet C (2005) Taking advantage of luminescent lanthanide ions. Chem Soc Rev
34:1048–1077
2. Kumar J et al (2015) Circularly polarized luminescence in chiral molecules and supramolecular
assemblies. J Phys Chem Lett 6:3445–3452
3. Sánchez-Carnerero EM et al (2015) Circularly polarized luminescence from simple organic
molecules. Chem Eur J 21:13488–13500
4. Emeis CA, Oosterhoff LJ (1967) Emission of circularly-polarised radiation by optically-active
compounds. Chem Phys Lett 1:129–132
5. Satrijo A et al (2006) Probing a conjugated polymer’s transfer of organization-dependent
properties from solutions to films. J Am Chem Soc 128:9030–9031
6. Wilson JN et al (2002) Chiroptical properties of poly(p-phenyleneethynylene) copolymers in
thin films: large g-values. J Am Chem Soc 124:6830–6831
7. Zhao Y et al (2016) Supramolecular chirality in achiral polyfluorene: chiral gelation, memory of
chirality, and chiral sensing property. Macromolecules 49:3214–3221
8. Dekkers HPJM, Closs LE (1976) The optical activity of low-symmetry ketones in absorption
and emission. J Am Chem Soc 98:2210–2219
9. Schippers PH, Dekkers HPJM (1983) Circular polarization of luminescence as a probe for
intramolecular 1nπà energy transfer in meso-diketones. J Am Chem Soc 105:145–146
10. Schippers PH et al (1983) Circular polarization in the fluorescence of β γ-enones: distortion
in the 1nπà state. J Am Chem Soc 105:84–89
11. Steinberg N et al (1981) Measurement of the optical activity of triplet-singlet transitions.
The circular polarization of phosphorescence of camphorquinone and benzophenone. J Am
Chem Soc 103:1636–1640
12. Phillips KES et al (2001) Synthesis and properties of an aggregating heterocyclic helicene.
J Am Chem Soc 123:11899–11907
13. Field JE et al (2003) Circularly polarized luminescence from bridged triarylamine helicenes.
J Am Chem Soc 125:11808–11809
14. Nakamura K et al (2014) Enantioselective synthesis and enhanced circularly polarized
luminescence of S-shaped double azahelicenes. J Am Chem Soc 136:5555–5558
216
T. Ikeda and T. Haino