Control of Excited-State Conformations in B,N-Acenes

Zhenpin Lu; Henrik Quanz; Julia Ruhl; Georg Albrecht; Christian Logemann; Derck Schlettwein; Peter R Schreiner; Hermann A Wegner

doi:10.1002/anie.201814104

Control of Excited-State Conformations in B,N-Acenes

Angew Chem Int Ed Engl. 2019 Mar 22;58(13):4259-4263. doi: 10.1002/anie.201814104. Epub 2019 Feb 20.

Authors

Zhenpin Lu^{1

2}, Henrik Quanz^{1

2}, Julia Ruhl^{1

2}, Georg Albrecht³, Christian Logemann⁴, Derck Schlettwein³, Peter R Schreiner^{1

2}, Hermann A Wegner^{1

2}

Affiliations

¹ Institute of Organic Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392, Giessen, Germany.
² Center for Materials Research (LaMa), Justus Liebig University, Heinrich-Buff-Ring 16, 35392, Giessen, Germany.
³ Institute of Applied Physics and Center for Materials Research (LaMa), Justus Liebig University, Heinrich-Buff-Ring 16, 35392, Giessen, Germany.
⁴ Institute of Inorganic Chemistry, Department of Chemistry, University of Cologne, Greinstr. 6, 50939, Köln, Germany.

PMID: 30657239
DOI: 10.1002/anie.201814104

Abstract

We present a new concept to control the conformations of molecules in the excited state through harvesting negative hyperconjugation. The strategy was realized with the 2,3,1,4-benzodiazadiborinane scaffold, which was prepared by a new synthetic procedure. Photochemical studies identified dual light emission, which was assigned to well-defined conformers. The emission at longer wavelength can be switched off by restricting the rotational degrees of freedom in the solid state as well as by controlling the energy levels of the excited states through adjusting the solvent polarity.

Keywords: B,N-heterocycles; azaborines; azobenzenes; dual fluorescence; synthetic methods.

Publication types

Research Support, Non-U.S. Gov't

Grants and funding

200021_143840/Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung/International