From a 1,2-azaborinine to large BN-PAHs via electrophilic cyclization

Synthesis, characterization and promising optical properties

authored by

Yannik Appiarius, Tim Stauch, Enno Lork, Pascal Rusch, Nadja C. Bigall, Anne Staubitz

Abstract

We present a convergent synthetic route towards boron-nitrogen containing polycyclic aromatic hydrocarbons (BN-PAHs) that allowed us to synthesize six derivatives. Starting from the conjunction of a 1,2-azaborinine nucleophile and various aryl electrophiles, the key step was the extension of the aromatic system via an electrophilic ring closure of the respective alkyne precursors. Our route allows the use of substituted PAH precursors to be circumvented, which are often unavailable. Instead, it builds up the BN-PAHs solely from easily accessible monocycles. All derivatives were emissive in solution and solid state with quantum yields up to Φlum = 0.40 and small Stokes shifts. The emission wavelengths in solid state were notably dependent on the connectivity of the rings. Due to excimer formation in one derivative, its emission was significantly redshifted with a comparatively slow secondary photoluminescence (PL) decay.

Organisation(s)

Institute of Physical Chemistry and Electrochemistry
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines

External Organisation(s)

University of Bremen

Type

Article

Journal

Organic Chemistry Frontiers

Volume

8

Pages

10-17

No. of pages

8

ISSN

2052-4110

Publication date

07.01.2021

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Organic Chemistry

Electronic version(s)

https://doi.org/10.1039/d0qo00723d (Access: Closed)