We report a mechanistic investigation of an aromatic dithioimide (2SS) displaying puzzling yet efficient photochemistry in ether solvents. Perplexingly, 2SS dissolved in ether solvents in a sealed and degassed vial was photochemically converted to the corresponding diimide (2OO), as determined by H NMR following product extraction. With no external sources of oxygen in the sample, could the oxygen in 2OO be from the ether itself? To study this unprecedented proposition, we attempt to uncover the ether's involvement in this reaction.
View Article and Find Full Text PDFWe report the synthesis and properties of a series of novel triphenylenedicarboxyimides and thioimides (-) to probe the effect of thionation on the formation of columnar mesophases. These materials display broad columnar mesophases and high clearing points and self-associate in solution to form dimers. Overall, thionation improved the self-assembly in solution and led to a stabilization of the columnar mesophase.
View Article and Find Full Text PDFThe synthesis and characterization of a novel series of dibenz[a,c]anthracenedicarboximides is reported. Incorporating electron-withdrawing imides bearing flexible alkyl chains allowed for the production of materials that self-assemble into hexagonal columnar mesophases featuring broad temperature ranges. Furthermore, longer N-alkyl chains or branched N-alkyl chains broaden the mesophase temperature range by lowering the melting transition without greatly influencing the clearing point.
View Article and Find Full Text PDFWe report the synthesis and characterization of a series of novel hexaalkoxydibenz[a,c]anthracenes. While the parent compound is not mesomorphic, the introduction of substituents in the 10- and 13-positions yields compounds with columnar liquid crystalline phases over very broad temperature ranges.
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