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Updated: Jul 23, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Late-Stage Aryl C-H Bond Cyclopropenylation with Cyclopropenium Cations
Hang-Fei Tu1, Aliénor Jeandin1,2, Corentin Bon3
1Institute of Chemical Research of Catalonia (ICIQ-CERCA), Barcelona Institute of Science and Technology, Av. Països Catalans, 16, 43007, Tarragona, Spain.
Abstract:
Herein, we disclose the first regio-, site- and chemoselective late-stage (hetero)aryl C-H bond cyclopropenylation with cyclopropenium cations (CPCs). The process is fast, operationally simple and shows an excellent functional group tolerance in densely-functionalized drug molecules, natural products, agrochemicals and fluorescent dyes. Moreover, we discovered that the installation of the cyclopropene ring in drug molecules could not only be used to shield against metabolic instability but also as a synthetic tool to reach medicinally-relevant sp3 -rich scaffolds exploiting the highly-strained nature of the cyclopropene ring with known transformations.
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