Oxidant-Induced Azolation of Electron-Rich Phenol Derivatives.

Since -arylazoles are widely present in natural products, pharmaceuticals, and functional materials, it is important to develop a simple and efficient synthetic method for the synthesis of -arylazoles. Herein, an oxidant-induced intermolecular azolation of phenol derivatives was demonstrated under catalyst-free condition. Both monoazolation and diazolation of phenols can be successfully achieved via this practical and powerful method.

Visible-Light-Induced C(sp)-H Oxidative Arylation with Heteroarenes.

Considering the ubiquitous C(sp)-H and the important value of alkylated heteroarenes, developing a universal method for C(sp)-H arylation with heteroarenes is significant. Herein, we proposed a method where Selectfluor can promote the oxidative C(sp)-H arylation with heteroarenes without external photocatalysis under visible-light irradiation. By EPR study, the N-F activation of Selectfluor by blue LED irradiation can generate the N radical cation, which is the key step for this conversion.

Visible light-induced direct α C-H functionalization of alcohols.

Considering the synthetic value of introducing active alcoholic hydroxyl group, developing C-H functionalization of alcohols is of significance. Herein, we present a photochemical method that under visible light irradiation, selectfluor can effectively promote the oxidative cross-coupling between alcohols and heteroarenes without the external photocatalysis, achieving the selective α sp C-H arylation of alcohol, even in the presence of ether. The N-F activation of selectfluor under blue LEDs irradiation is evidenced by electron paramagnetic resonance (EPR) study, which is the key process for the oxidative activation of α sp C-H alcohols.

Visible light-mediated oxidative C(sp)-H phosphonylation for α-aminophosphonates under oxidant-free conditions.

An external oxidant-free synthesis of α-aminophosphonates by synergistically combining photocatalysis and proton-reduction catalysis is developed herein. The gram-scale experiment demonstrates the potential utility of this protocol. This study may have important implications for the functionalization of oxidant-sensitive C(sp)-H bonds.