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Updated: May 12, 2025

Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
Rhodium(III)-Catalyzed Redox-Neutral [4 + 2] Annulation of 3,5-Diaryloxadiazoles with Alkynes: A Dual C-H Activation
Siyuan Li1, Yinsong Han1, Zhen Yang1
1Zhejiang Province Key Laboratory of Traditional Process Substitution Technology for Fin Chemicals, College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing 312000, China.
Abstract:
A rhodium(III)-catalyzed dual-ring formation via cascade C-H activation/[4 + 2] annulation of 3,5-diaryoxadiazoles with alkynes was developed. This strategy has been demonstrated with a variety of 3,5-diaryloxadiazoles and alkynes, and it has been successfully scaled up to gram-scale synthesis, highlighting its potential significance in the direct construction of C-N atropisomers. Furthermore, the cleavage of the N-O bond is essential for the formation of the bicyclic structure in the absence of an external oxidant. Mechanistic studies revealed that cleavage of the C-H bond at the 3-phenyl group of oxadiazole was likely a rate-determining step in this reaction.
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