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Updated: Sep 17, 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
Aromatic C-H Thioalkylphosphinylation of [2.2]Paracyclophanes via Sulfonium Salts
Mingrui Li1,2, Juan Ma2, Liandi Wang2
1School of Chemistry and Material Science, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China.
Abstract:
Base-enabled aromatic C-H functionalization of [2.2]paracyclophanes was achieved by thioalkylphosphinylation via sulfonium salts. Cross-coupling between [2.2]paracyclophane tetrahydro-1H-thiophen-1-ium trifluoromethanesulfonates and secondary phosphine oxides afforded thioalkylphosphinylated [2.2]paracyclophane derivatives through selective C(sp3)-S bond cleavage of the arylsulfonium salts under mild conditions. The protocol features broad substrate scopes, good functional group tolerance from readily available reagents, and decent efficiency in up to 96% yields. The practicability of this method was demonstrated by scale-up preparation of the target products and their transformations to potential P,S-ligands for Suzuki and Sonogashira cross-coupling reactions.
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