Synthesis and Structural Elucidation of Diversely Functionalized 5,10-Diaza[5]Helicenes
作者:Deepali Waghray、Jing Zhang、Jeroen Jacobs、Wienand Nulens、Nikola Basarić、Luc Van Meervelt、Wim Dehaen
DOI:10.1021/jo301814m
日期:2012.11.16
building block via Wittig reaction followed by photochemical electrocyclization. The helicene skeleton was substituted by a variety of O-, S-, N-, and C-centered nucleophiles using nucleophilic aromatic substitution reactions and palladium-catalyzed reactions like Suzuki coupling and Buchwald–Hartwig aminations. We have determined, using X-ray single-crystal diffraction, the crystal structures of the chloro-
In the present study, carbazole-based diaza[6]helicenes were synthesized utilizing versatile quinoline and 9-(2-ethylhexyl)-2,7-dimethoxycarbazole-3-carbaldehyde building blocks via the Wittig reactionphotocyclization strategy. The presence of bifunctional units comprising electrophilic chloroquinoline and electron-rich carbazole has opened up new opportunities. The chloro group was substituted with a chiral amine, allowing diastereomeric separation, and the chiral forms were monofunctionalized via electrophilic substitution on the carbazole unit. Postcyclization functionalization via substituting the carbazole unit provides a platform for the synthesis of chiral functionalized materials with potential application in fields such as asymmetric synthesis and organic electronics. The configuration of the diaza[6]helicene diastereomers was demonstrated by time-dependent density functional theory (TD-DFT) calculations. Furthermore, on the basis of the DFT calculations of the HOMO-LUMO energy levels of the chiral forms, these compounds can be potentially of interest as hole-transporting compounds
Intermolecular interactions in molecular crystals and their effect on thermally activated delayed fluorescence of helicene-based emitters
作者:Anastasia Klimash、Piotr Pander、Wim T. Klooster、Simon J. Coles、Przemyslaw Data、Fernando B. Dias、Peter J. Skabara
DOI:10.1039/c8tc03390k
日期:——
In crystals of donor–acceptor helicene molecules, thermally activated delayed fluorescence (TADF) is strongly enhanced by the presence of occluded hexane molecules.