Intramolecular borylation via sequential B-Mes bond cleavage for the divergent synthesis of B,N,B-doped benzo[4]helicenes
Abstract
New symmetric and unsymmetric B,N,B-doped benzo[4]helicenes 3 - 6a/b have been achieved in good yields, using a three-step process, starting from N(tolyl)3 in a highly divergent manner (7 examples). A borinic acid functionalized 1,4-B,N- anthracene 1 was found to display unprecedented reactivity, acting as a convenient and highly effective precursor for selective formation of bromo substituted B,N,B-benzo[4]helicenes 2a/2b via intramolecular borylation and sequential B-Mes bond cleavage in presence of BBr3. Subsequent reaction of 2a/2b with Ar-Li provided a highly effective toolbox for the preparation of symmetrically/unsymmetrically functionalized B,N,B-helicenes. Their high photoluminescence quantum yields along with the small ∆EST suggest the potential as thermally activated delayed fluorescence (TADF) emitters for organic light-emitting diodes (OLEDs).
Citation
Knöller , J , Meng , G , Wang , X , Hall , D , Pershin , A , Beljonne , D , Olivier , Y , Laschat , S , Zysman-Colman , E & Wang , S 2020 , ' Intramolecular borylation via sequential B-Mes bond cleavage for the divergent synthesis of B,N,B-doped benzo[4]helicenes ' , Angewandte Chemie International Edition , vol. Early View . https://doi.org/10.1002/anie.201912340
Publication
Angewandte Chemie International Edition
Status
Peer reviewed
ISSN
1433-7851Type
Journal article
Rights
Copyright © 2020 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the author created accepted manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1002/anie.201912340
Description
Authors thank the Natural Sciences and Engineering Research Council of Canada and the Leverhulme Trust (RPG-2016-47) for financial support. J. A. Knöller thanks the Baden Württemberg Stiftung for a scholarship as well as Queen's and Stuttgart University for enabling this research through the Dual Degree Masters program.Collections
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