10 Circularly Polarized Luminescence (CPL) Based on Planar …
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25 (Fig. 10.12) (Morisaki et al. 2015). Moderate CPL was observed (Fig. 10.13), and
the Φ PL and |g lum | values were estimated to be 0.07 and 5 × 10
−4 , respectively.
Chromatographic optical resolutions of pseudo-ortho-disubstituted [2.2]paracyclophanes were reported by Lützen (Meyer-Eppler et al. 2013) and Hasegawa
(Kobayakawa et al. 2014; Hasegawa et al. 2017, 2019; Ishioka et al. 2019), and
several enantiopure π-stacked molecules have been produced. Figure 10.14 shows
the (R p )-isomers prepared by Hasegawa and coworkers (Kobayakawa et al. 2014;
Hasegawa et al. 2017; Hasegawa et al. 2019; Ishioka et al. 2019). Although the CPL
properties of these compounds were not reported, their interesting chiroptical and
electrochemical properties were shown. Compound 27 was used as a chiral dopant for
nematic liquid crystals with a helical twisting power of around 10 m
−1 (Kobayakawa
et al. 2014), and 28 (Hasegawa et al. 2017) and 29 (Hasegawa et al. 2019) exhibited
Fig. 10.12 Synthesis of optically active polymer consisting of [2.2]paracyclophane and quaterthiophene
Fig. 10.13 CPL and PL
spectra of (R p )- and (S p )-26
in CHCl 3 (10 × 10 −5 M)
excited at 380 nm for CPL
and λ abs,max for PL