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Updated: Aug 23, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Cobalt(II)-Catalyzed Directed C-H Functionalization/[3+2] Annulation of N-Arylguanidines with Alkynes
Harish Parihar1, Natesan Thirupathi1
1Department of Chemistry, University of Delhi, Delhi 110 007, India.
Abstract:
A family of N,N'-diaryl-N″-(quinolin-8-yl)guanidines were prepared by two methods, and these guanidines were subjected to Co(II)-catalyzed C-H functionalization/annulation with terminal and internal alkynes under mild conditions to afford a family of indole guanidines. Substrates with a range of electronic and steric properties were tolerated. The fluxional behavior of two guanidines and molecular structures of nine compounds are reported. Several key experiments were carried out to support the proposed mechanism of alkyne annulation.
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