Intramolecular C-H insertion vs. Friedel-Crafts coupling induced by silyl cation-promoted C-F activation

Abstract

Silyl cation-promoted aryl C-F activation can lead to formal C-H activation and the formation of new C(ar)-C(alkyl) bonds. Deuterium-labeling experiments suggest an insertion of a phenyl cation into the C-H bond. From competition experiments, a relation between reaction rate and C-H bond strength could be established. Mechanistic parallels are drawn to the Mascarelli reaction.