Gold-catalyzed allene cycloisomerization for pyrrole synthesis: towards highly fluorinated BODIPY dyes
Linda Lempke1, Tobias Fischer, Jérémy Bell
1Organic Chemistry, Dortmund University of Technology, Otto-Hahn-Str. 6, D-44227 Dortmund, Germany. norbert.krause@tu-dortmund.de.
Abstract:
A novel synthetic strategy toward highly fluorinated BODIPY dyes with exceptional photostabilities relying on sustainable gold catalysis has been developed. A key to the tailored pyrrole precursors is the gold catalysis performed in ionic liquids as the reaction medium, allowing a facile recycling of the catalysts. The dyes prepared are well-matching with the spectral windows of popular rhodamine dyes and possess high brightness while showing a distinctly higher photostability than the rhodamines especially in aprotic solvents.
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