Circularly polarized luminescence and high photoluminescence quantum yields from rigid 5,10-dihydroindeno[2,1- a]indene and 2,2'-dialkoxy-1,1'-binaphthyl conjugates and copolymers

Keisuke Iwata; Makoto Tsurui; Kosuke Itaya; Naoto Hamaguchi; Yasunobu Egawa; Yuichi Kitagawa; Yasuchika Hasegawa; Hayato Tsuji

doi:10.1039/d4ra00380b

Circularly polarized luminescence and high photoluminescence quantum yields from rigid 5,10-dihydroindeno[2,1- a]indene and 2,2'-dialkoxy-1,1'-binaphthyl conjugates and copolymers

RSC Adv. 2024 Feb 29;14(11):7251-7257. doi: 10.1039/d4ra00380b.

Authors

Keisuke Iwata¹, Makoto Tsurui², Kosuke Itaya², Naoto Hamaguchi¹, Yasunobu Egawa¹, Yuichi Kitagawa², Yasuchika Hasegawa², Hayato Tsuji¹

Affiliations

¹ Department of Chemistry, Faculty of Science, Kanagawa University 3-27-1 Rokkaku-bashi, Kanagawa-ku Yokohama 221-8686 Japan tsujiha@kanagawa-u.ac.jp.
² Faculty of Engineering, Hokkaido University Kita13 Nishi8, Kita-ku Sapporo 060-8628 Japan.

Abstract

5,5,10,10-Tetramethyl-5,10-dihydroindeno[2,1-a]indene (COPV1(Me)) was installed into either the 3,3'- or 6,6'-positions of chiral 2,2'-dioctyloxy-1,1'-binaphthyl to afford 2 : 1 conjugates (monomeric compounds) and 1 : 1 copolymers. These compounds showed high photoluminescence quantum yields of >0.95 whilst also exhibiting circular dichroism (CD) and circularly polarized luminescence (CPL). The dissymmetry factors of CPL (g_CPL) for the 3,3'- and 6,6'-monomeric compounds in THF were 6.6 × 10^-4 and 3.3 × 10^-4, respectively. The 3,3'-isomer has a higher g value than the 6,6'-isomer, which was attributed to the difference in the extent of π-conjugation and the angle between electronic and magnetic transition moments. The g_CPL values of the 3,3'-linked and 6,6'-linked copolymers were 1.1 × 10^-3 and 6.8 × 10^-4, respectively. The structural rigidity of the COPV units is beneficial to achieve relatively high g values whilst maintaining a photoluminescence quantum yield that is close to unity by using a single type of fluorophore.