Synthesis 2021; 53(09): 1584-1596
DOI: 10.1055/a-1343-5810
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Peripherally Donor-Installed 7,8-Diaza[5]helicenes as a Platform for Helical Luminophores

Yuta Ikari
a   Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 5650871, Japan
,
Takahito Kaihara
a   Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 5650871, Japan
,
Shimpei Goto
a   Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 5650871, Japan
,
Marcel Bovenkerk
b   Institute for Organic Chemistry, University of Freiburg, Alberstraße 21, 79104 Freiburg, Germany
,
David C. Grenz
b   Institute for Organic Chemistry, University of Freiburg, Alberstraße 21, 79104 Freiburg, Germany
,
Birgit Esser
b   Institute for Organic Chemistry, University of Freiburg, Alberstraße 21, 79104 Freiburg, Germany
,
Marli Ferreira
c   Faculty of Chemistry, Silesian University of Technology, M. Strzody 9, 44-100 Gliwice, Poland
,
Patrycja Stachelek
d   Chemistry Department, Durham University, South Road, Durham DH1 3LE, United Kingdom
,
Przemyslaw Data
c   Faculty of Chemistry, Silesian University of Technology, M. Strzody 9, 44-100 Gliwice, Poland
e   Center of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Sklodowskiej 34, 41-819 Zabrze, Poland
,
Takumu Yoshida
f   Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
,
Tomoyuki Ikai
g   Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan
,
Norimitsu Tohnai
a   Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 5650871, Japan
,
a   Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 5650871, Japan
,
Youhei Takeda
a   Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 5650871, Japan
› Author Affiliations
This work was partly supported by a Grant-in-Aid for Scientific Research on Innovative Areas ‘π-System Figuration: Control of Electron and Structural Dynamism for Innovative Functions’ (JSPS KAKENHI Grant Number JP17H05155, to Y.T.), ‘Aquatic Functional Materials: Creation of New Materials Science for Environment-Friendly and Active­ Functions’ from the MEXT (JSPS KAKENHI Grant Number JP19H05716, to Y.T.), by a Grant-in-Aid for Scientific Research (B) (JSPS KAKENHI Grant Number JP20H02813), and by the Research Grants from the Japan Prize Foundation, the Iketani Science and Technology Foundation, and the Research Encouragement Grants and the Continuation Grants for Young Researchers from the Asahi Glass Foundation (to Y.T.). Y.T., P.D., and P.S. acknowledge the EU’s Horizon 2020 for funding the OCTA project under grant agreement No 778158. P.D. and M.F. acknowledge the support received from the First Team program of the Foundation for Polish Science co-financed by the European Union under the European Regional Development Fund (project number: POIR.04.04.00-00-4668/17-00). B.E., D.C.G., and M.B. thank the Deutsche Forschungsgemeinschaft (German Research Foundation; Emmy Noether grant ES 361/2-1 and grant No. INST 40/467-1 FUGG) and the state of Baden-Württemberg through bwHPC for financial support.


Abstract

A new family of emissive donor–acceptor–donor (D-A-D) compounds has been developed by introducing two electron donors into the 7,8-diaza[5]helicene core as a novel helical electron acceptor. The X-ray crystallographic analyses revealed the uniquely twisted and helical structures of these compounds in the solid states. Notably, some D-A-D compounds developed herein display distinct mechanochromic luminescence (MCL) in the solid state, and a D-A-D helicene shows circularly polarized luminescence (CPL) with a relatively high luminescence dissymmetry factor g lum of ca. 10–3. Time-resolved spectroscopic analysis revealed the aspects of thermally activated delayed fluorescence characters of the helicenes. Furthermore, the emissive helicenes were applied to organic light-emitting diodes as emitters.

Supporting Information



Publication History

Received: 01 December 2020

Accepted after revision: 28 December 2020

Accepted Manuscript online:
28 December 2020

Article published online:
28 January 2021

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