Invited Speaker

Prof. Yasuhiro Morisaki

Prof. Yasuhiro Morisaki

School of Biological and Environmental Sciences
Kwansei Gakuin University, Japan
Speech Title: Synthesis of Circularly Polarized Luminescence Emitters Based on Planar Chiral [2.2]Paracyclophanes

Abstract: [2.2]Paracyclophane is a common cyclophane compound consisting of face-to-face benzene rings fixed by ethylene chains at the para-positions. Two eclipsed benzene rings are closely stacked, causing suppression of their rotatory motion. [2.2]Paracyclophane compounds with one or more substituents are planar chiral compounds depending on the substitution position(s). Enantiopure [2.2]paracyclophane compounds have been employed mainly as chiral ligands and chiral auxiliaries in organometallic and organic chemistry, respectively. However, there are only a few examples of their applications in the fields of polymer and materials chemistry [1]. Recently, we achieved optical resolutions of six kinds of di- and tetrasubstituted [2.2]paracyclophanes by the diastereomer method using appropriate chiral auxiliaries [2]. Subsequently, we synthesized various optically active molecules [3] containing planar chiral [2.2]paracyclophane units; the obtained chiral molecules exhibited excellent circularly polarized luminescence (CPL) properties.

We introduce syntheses of optically active cyclic oligomers [4] and macromolecules [5] based on the planar chiral [2.2]paracyclophanes as chiral building blocks. Their synthetic procedures and chiroptical properties, in particular good CPL profiles, are disclosed.

Keywords: Circularly polarized luminescence (CPL), cyclic oligomer, macrocycle, [2.2]Paracyclophane, planar chirality.

References:
[1] Bull. Chem. Soc. Jpn. 2019, 92, 265-274.
[2] For example: (a) J. Am. Chem. Soc. 2014, 136, 3350-3353. (b) Chem. Commun. 2021, 57, 9256-9259. (c) J. Mater. Chem. C 2023, 11, 986-993.
[3] For recent examples: (a) Chem. Asian J. 2022, 17, e202200418. (b) Bull. Chem. Soc. Jpn. 2022, 95, 1353-1359e. (c) Science 2022, 377, 673-678.
[4] (a) Chem. Asian J. 2022, 17, e202101267. (b) Chem. Eur. J. 2023, 29, e202203533.
[5] (a) Bull. Chem. Soc. Jpn. 2022, 95, 110-115. (b) Adv. Funct. Mater. in press (DOI: 10.1002/adfm.202310566).


Biography: Yasuhiro Morisaki is Professor at Kwansei Gakuin University. He graduated from Kyoto University in 1995, and then, he received Ph.D. from Kyoto University in 2000. After a six-month postdoctoral stay at Osaka National Research Institute (currently called as National Institute of Advanced Industrial Science and Technology (AIST) Kansai), he became Assistant Professor at Kyoto University in 2000. From 2004 to 2005, he carried out postdoctoral work at the University of Alberta, Canada. He became lecturer at Kyoto University in 2008 and full Professor at Kwansei Gakuin University in 2015. His research interests focus on polymer and organic synthesis, in particular, synthesis of functional molecules based on planar chiral cyclophane for opto-electronic materials.