The incorporation of main group elements into conjugated materials is known to result in unusual properties and to enable new functions. In particular, the ability of tricoordinate boron to participate in p-delocalization can have a dramatic effect on the optoelectronic properties of conjugated materials by selectively lowering the LUMO orbital levels. The electron-deficient character of boron also enables the reversible formation of Lewis pairs (LPs) by interaction of Lewis acids with Lewis bases.
In our recent work, we have explored the incorporation of boron into conjugated oligomers, macrocycles, and polymers for optoelectronic applications. We have also demonstrated that base-directed electrophilic aromatic C-H borylation provides an effective means to generate luminescent B-N containing conjugated materials with unusual properties such as self-sensitized singlet oxygen generation.
On the other hand, the judicious decoration of polymers with organoborane Lewis acid sites can be exploited in sensory and stimuli-responsive materials, as well as the development of supported catalysts that rely on the ability of Lewis acids to activate small molecules. In addition, we have discovered that “smart” dynamic materials can be generated by embedding both Lewis acid and base sites into polymer networks.
In this talk I will discuss some of these discoveries and highlight their impact in diverse application fields ranging from organic electronic materials and chemosensors to reprocessible elastomers and supported catalysts.
- (a) Main Group Strategies towards Functional Hybrid Materials, T. Baumgartner, F. Jäkle, Eds. John Wiley & Sons Ltd, Chichester, 2018; (b) F. Vidal, F. Jäkle, Angew. Chem. Int. Ed. 2019, 58, 5846.
- (a) B. Meng, Y. Ren, J. Liu, F. Jäkle, L. Wan, Angew. Chem. Int. Ed. 2018, 57, 2183; (b) N. Baser-Kirazli, R. A. Lalancette, F. Jäkle, Angew. Chem. Int. Ed. 2020, 59, 8689.
- (a) K. Liu, R. A. Lalancette, F. Jäkle J. Am. Chem. Soc. 2019, 141, 7453; (b) M. Vanga, R. A. Lalancette, F. Jäkle Chem. Eur. J. 2019, 25, 10133.
- (a) F. Cheng, E. M. Bonder, F. Jäkle, J. Am. Chem. Soc. 2013, 135, 17286; (b) F. Vidal, J. McQuade, R. A. Lalancette, F. Jäkle, J. Am. Chem. Soc. 2020, 142, DOI: 10.1021/jacs.0c05454; (c) H. Lin, S. Patel, F. Jäkle, Chem. Eur. J. 2020, submitted.
- F. Vidal, J. Gomezcoello, R. A. Lalancette, F. Jäkle, J. Am. Chem. Soc. 2019, 141, 15963.
Frieder Jäkle is a Distinguished Professor in the Department of Chemistry at the Newark Campus of Rutgers University. He received his Diploma in 1994 and Ph.D. in 1997 from TU München, Germany, under the direction of Prof. Wagner. After a postdoctoral stint with Prof. Manners at the University of Toronto he joined Rutgers University in 2000. His research interests revolve around main group chemistry as applied to materials and catalysis, encompassing projects on organoborane Lewis acids, conjugated hybrid materials, luminescent materials for optoelectronic and sensory applications, stimuli-responsive and supramolecular polymers. He is the recipient of an NSF CAREER award (2004), an Alfred P. Sloan fellowship (2006), a Friedrich Wilhelm Bessel Award of the Alexander von Humboldt Foundation (2009), the ACS Akron Section Award (2012), the Boron Americas Award (2012) and the Board of Trustees Research Award at Rutgers University (2017). In 2019 he was named a Fellow of the American Chemical Society. He has served on the editorial advisory boards of several journals, including Macromolecules, ACS Macro Letters, and Organometallics.