Binaphthyl-Bridged Pyrenophanes: Intense Circularly Polarized Luminescence Based on a D2 Symmetry Strategy

Kazuto Takaishi; Sho Murakami; Fumiya Yoshinami; Tadashi Ema

doi:10.1002/anie.202204609

Binaphthyl-Bridged Pyrenophanes: Intense Circularly Polarized Luminescence Based on a D₂ Symmetry Strategy

Angew Chem Int Ed Engl. 2022 Jul 4;61(27):e202204609. doi: 10.1002/anie.202204609. Epub 2022 May 12.

Authors

Kazuto Takaishi¹, Sho Murakami¹, Fumiya Yoshinami¹, Tadashi Ema¹

Affiliation

¹ Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tsushima, Okayama, 700-8530, Japan.

PMID: 35478428
DOI: 10.1002/anie.202204609

Abstract

A series of D₂ -symmetric macrocycles composed of alternately linked pyrene and binaphthyl moieties (binaphthyl-bridged pyrenophanes) have been synthesized. Among them, a pyrenophane possessing ether linkers at the 2,7-positions of the pyrenes exhibited intense circularly polarized luminescence (CPL) with a |g_lum | value of 0.053. This value is by far the highest for excimers and was not sensitive to temperature, solvent, or concentration. The CPL originated from a twisting pyrene excimer, with the (R)-binaphthyl moieties producing a left-handed twist excimer, which exhibited (-)-CPL. The electric and magnetic transition dipole moments are perfectly parallel, which is the best relationship for strong CPL.

Keywords: Axial Chirality; Biaryls; Circularly Polarized Luminescence; Conformation Analysis; Excimers.

Abstract

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