Oxone® Mediated Regioselective C(sp2)−H Selenylation and Thiocyanation of Pyrazolo[1,5-a]pyrimidines at Room Temperature

Abstract

A mild Oxone® mediated reaction for direct regioselective C−H selenylation and thiocyanation of pyrazolo[1,5-a]pyrimidines is established at ambient temperature. This practical and efficient methodology employs Oxone® as a user friendly, green, non-toxic and cheap reagent to facilitate selenylation and thiocyanation at room temperature. The present method offers high regioselectivity, broad substrate scope, mild conditions and excellent yields. Further, this eco-friendly approach could easily be extended for mild C−H selenylation and thiocyanation of other heterocycles. Mechanistic studies indicate that the reaction occurs through electrophilic substitution mechanism via generation of an electrophilic chalcogen species. © 2024 Wiley-VCH GmbH.