A promising approach to new pi-conjugated materials with enhanced properties is to introduce heteroatoms, either embedded into the conjugated backbone or attached at the periphery. Interaction of the empty p orbital on boron with an organic pi-system results not only in strongly enhanced electron acceptor properties, but also very interesting optical characteristics. The resulting desirable optical and electronic characteristics can be exploited, for example, in linear and non-linear optical materials, emission and electron conduction layers in organic light emitting devices (OLEDs), and new probes and sensors for anions.[1] In this presentation we will share our recent advances on the development of conjugated macrocycles and polymers that contain highly electron-deficient organoborane moieties. Specifically, we will introduce a new class of ambipolar oligomers and macrocycles that feature both electron-deficient arylborane and electron-rich arylamine moieties and discuss their one- and two-photon excitation characteristics.[2] In addition, we will elaborate on a new set of perfectly air-stable yet highly electron-deficient dithienylboranes as building blocks for conjugated polymers with highly coplanar structures and tunable luminescence characteristics.[3]
[1] a) C. D. Entwistle, T. B. Marder, Chem. Mater. 2004, 16, 4574; b) F. Jäkle, Chem. Rev. 2010, 110, 3985 ; c) A. Doshi and F. Jäkle, Chapter 1.30 in Jan Reedijk, Kenneth Poeppelmeier, editors. Comprehensive Inorganic Chemistry II, Vol 1. Oxford: Elsevier; 2013, p 861-891; "Boron-Containing Polymers".
[2] P. Chen and F. Jäkle J. Am. Chem. Soc. 2011, 133, 20142; P. Chen, R. A. Lalancette and F. Jäkle, Angew. Chem. Int. Ed. 2012, 51, 7994; P. Chen, X. Yin, N. Baser, F. Jäkle, to be submitted.
[3] X. Yin, J. Chen, R. A. Lalancette, T. B. Marder, and F. Jäkle, Angew. Chem. Int. Ed. 2014, 53, 9761; X. Yin, F. Guo, F. Jäkle, to be submitted.