Design, Synthesis, and Characterization of Functionalized Silepins: High Quantum Yield Blue Emitters
作者:Lauren G. Mercier、Shunsuke Furukawa、Warren E. Piers、Atsushi Wakamiya、Shigehiro Yamaguchi、Masood Parvez、Ross W. Harrington、William Clegg
DOI:10.1021/om2000597
日期:2011.3.28
The synthesis of a family of 1,1-dimethyldibenzo[b,f]silepin derivatives, substituted with donor groups of various donor strength and conjugation length in the positions meta or para to the silepin silicon, is presented. The compounds were characterized by NMR, UV−vis, and fluorescence spectroscopy, as well as with cyclic voltammetry and DFT computations. One of the meta series was characterized by
Functionalized Dibenzoborepins as Components of Small Molecule and Polymeric π-Conjugated Electronic Materials
作者:Anthony Caruso、John D. Tovar
DOI:10.1021/jo2001726
日期:2011.4.1
We present the synthesis and characterization of dibenzo[b,f]borepins (DBBs) functionalized at the para and meta position with respect to the boron center in order to understand how regiochemical issues influence photophysical and electrochemical properties. An expanded synthetic repertoire is presented, using palladium catalysis (to perform Stifle, Suzuki, Buchwald- Hartwig, and Sonogashira cross-coupling reactions) and lithium halogen exchange to synthesize a series of extended a-conjugated DBBs. These chemistries are enabled by the use of a sterically bulky Mes* (2,4,6-tri-tert-butylphenyl) group on boron and the inclusion of reactive bromide handles on the DBB core. Photophysical, electrochemical, and computational analyses of these compounds indicate that relative to the protio-DBB the installation of groups at the meta positions decreases the optical band gap while para substitution raises the electron affinity of the system. Thus, both the HOMO-LUMO gap and specific frontier molecular orbital levels can be tuned by the installation of different conjugated substituents.