The direct para-selective functionalization of arenes is difficult under mild conditions without the use of directing groups and transition-metal catalysts. Here we present a fluorosulfuryl imidazolium triflate-mediated direct para-selective C-H arylation and alkylation of N-arylhydroxylamines. This protocol exhibits a broad substrate scope and great functional-group adaptability. Moreover, the potential for scalable production and the feasibility of further modifications of the products showcase the practical utility of this method in synthetic applications.
Jiao et al. (2026) studied this question.