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Updated: Jul 7, 2026
Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides
Published on: November 21, 2013
Synthesis, chiroptical properties, and solid-state structure determination of two new chiral dipyrrin difluoroboryl
Albert Gossauer1, Freddy Nydegger, Tibor Kiss
1Chemiedepartement der Universität, Ch. du Musée 9, CH-1700 Fribourg, Switzerland. albert.gossauer@unifr.ch
Abstract:
Two new types of optically active BODIPY fluorophores bearing chiral phenyl substituents either at the meso-position or at both external alpha-positions have been synthesized. Their chiroptical properties are strongly dependent both on the position of the chiral group and on the protonation of the chromophore. The solid-state structures of one of the difluoroboryl chelates bearing the chiral phenyl substituent at the meso-position (9a) as well as of the corresponding ligand (8a) and its perchlorate have been determined by X-ray diffraction analysis. These are, to the best of our knowledge, the first crystal structures of a dipyrrin free base and of a dipyrrin salt which have been obtained by X-ray diffraction analysis. Hence, for the first time, the helical structure of a protonated dipyrrin chromophore has been proved experimentally.
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