Potential Switchable Circularly Polarized Luminescence
from Chiral Cyclometalated Platinum(II) Complexes
Xiao-Peng Zhang
Victoria Y. Chang
Jian Liu
Xiao-Liang Yang
Wei Huang
Yizhi Li
Cheng-Hui Li
Gilles Muller
Xiao-Zeng You
10.1021/ic5019136.s001
https://acs.figshare.com/articles/journal_contribution/Potential_Switchable_Circularly_Polarized_Luminescence_from_Chiral_Cyclometalated_Platinum_II_Complexes/2046657
A series of chiral
cyclometalated platinum(II) complexes, [Pt((−)-L<sub>1</sub>)(Dmpi)]Cl ((−)-<b>1</b>), [Pt((+)-L<sub>1</sub>)(Dmpi)]Cl
((+)-<b>1</b>), [Pt((−)-L<sub>2</sub>)(Dmpi)]Cl ((−)-<b>2</b>), [Pt((+)-L<sub>2</sub>)(Dmpi)]Cl ((+)-<b>2</b>),
[Pt<sub>3</sub>((−)-L<sub>2</sub>)<sub>2</sub>(Dmpi)<sub>4</sub>](ClO<sub>4</sub>)<sub>4</sub> ((−)-<b>3</b>), and [Pt<sub>3</sub>((+)-L<sub>2</sub>)<sub>2</sub>(Dmpi)<sub>4</sub>](ClO<sub>4</sub>)<sub>4</sub> ((+)-<b>3</b>) [(−)-L<sub>1</sub> = (−)-4,5-pinene-6′-phenyl-2,2′-bipyridine,
(+)-L<sub>1</sub> = (+)-4,5-pinene-6′-phenyl-2,2′-bipyridine),
(−)-L<sub>2</sub> = (−)-1,3-bis(2-(4,5-pinene)pyridyl)benzene,
(+)-L<sub>2</sub> = (+)-1,3-bis(2-(4,5-pinene)pyridyl)benzene, Dmpi
= 2,6-dimethylphenyl isocyanide], have been designed and synthesized.
In aqueous solutions, (−)-<b>1</b> and (+)-<b>1</b> aggregate into one-dimensional helical chain structures through
Pt···Pt, π–π, and hydrophobic–hydrophobic
interactions. (−)-<b>3</b> and (+)-<b>3</b> represent
a novel helical structure with Pt–Pt bonds. The formation of
helical structures results in enhanced and distinct chiroptical properties
as evidenced by circular dichroism spectra. Circularly polarized luminescence
(CPL) was observed from the aggregates of (−)-<b>1</b> and (+)-<b>1</b> in water, as well as (−)-<b>3</b> and (+)-<b>3</b> in dichloromethane. The CPL activity can
be switched reversibly (for (−)-<b>1</b> and (+)-<b>1</b>) or irreversibly (for (−)-<b>3</b> and (+)-<b>3</b>) by varying the temperature.
2015-12-17 06:46:16
chiroptical properties
helical chain structures
Pt
Potential Switchable Circularly Polarized Luminescence
dichroism spectra
CPL activity
helical structures results
novel helical structure