Metallaphotoredox catalysis for sp³C–H functionalizations through hydrogen atom transfer (HAT)

Abstract

sp3 C–H functionalizations under the combination of photocatalytic HAT and transition metal catalysis.

The multiple roles of rare earth elements in the field of photocatalysis

“…5 In the following decades, photocatalytic technology has developed rapidly. 6–11 People have discovered that photocatalytic reactions play significant roles in many research fields, including photocatalytic CO 2 reduction, pollutant degradation, multi-carbon-based material synthesis, water pollution control, and others. 12–22 The mechanism of the photocatalytic reaction has also been confirmed by scientists: when a beam of light is irradiated on the semiconductor photocatalyst, the energy of the incident light ( hυ ) is higher than the forbidden bandwidth ( E g ) of the semiconductor, the electrons (e − ) in the valence band are excited to transition to the conduction band, and at the same time, the valence band produces holes (h + ), and under the action of the electric field, the e − and h + diffuse to the surface of the catalyst, and the e − and h + are separated efficiently so that the conduction band and the valence band have the capacity to oxidize and reduce, respectively, which can have a redox reaction with the surface adsorption of the material to produce a product in line with the expectation of the people.…”

Origin of site-selectivity of hydrogen atom transfer in carbohydrate C–H alkylations via photoredox catalysis

“…9 Subsequently, the quinuclidine radical cation derived from the photoredox cycle 10 would abstract one hydrogen atom from the pyranoid ring via the hydrogen atom transfer (HAT) mechanism. 11 The generated glycosyl radical II could be trapped by the electron-deficient alkene through Giese addition. 12 Intermediate III would be reduced and protonated to give IV , which is followed by intramolecular lactonization, finally delivering the C–H alkylation product 3 .…”

Copper-Catalyzed, Interrupted Remote Fluoromethylthiolation of Unactivated C(sp3)-H Bonds

“…C–H bonds are ubiquitous in organic molecules, and functionalization of the C–H bond has been attractive for the late-stage modification of pharmaceutical molecules . In the past several years, a few difluoromethylthiolations of C–H bonds were reported.…”