Electrochemical Activation of Diverse Conventional Photoredox Catalysts Induces Potent Photoreductant Activity**
作者:Colleen P. Chernowsky、Alyah F. Chmiel、Zachary K. Wickens
DOI:10.1002/anie.202107169
日期:2021.9.20
Herein, we disclose that electrochemical stimulation induces new photocatalytic activity from a range of structurally diverse conventional photocatalysts. These studies uncover a new electron-primed photoredox catalyst capable of promoting the reductive cleavage of strong C(sp2)−N and C(sp2)−O bonds. We illustrate several examples of the synthetic utility of these deeply reducing but otherwise safe
Photocatalytic Conversion of Benzyl Alcohols/Methyl Arenes to Aryl Nitriles via H‐Abstraction by Azide Radical
作者:Maniklal Shee、Sk. Sheriff Shah、N. D. Pradeep Singh
DOI:10.1002/chem.202001332
日期:2020.11.6
aryl nitriles from easily accessible alcohols or methyl arenes in the presence of O2. Organic photoredox catalyst, 4CzIPN (1,2,3,5‐tetrakis(carbazol‐9‐yl)‐4,6‐dicyanobenzene), induces single electron transfer (SET) fromazide N3− and generates azide radical N3⋅.The photogenerated N3⋅ abstracts H atom from α‐C−H bond of benzylic system, which provides aldehyde and hydrazoic acid (HN3) in situ. This
Photoinduced Hydrocarboxylation via Thiol-Catalyzed Delivery of Formate Across Activated Alkenes
作者:Sara N. Alektiar、Zachary K. Wickens
DOI:10.1021/jacs.1c07562
日期:2021.8.25
Herein we disclose a new photochemical process to prepare carboxylic acids from formate salts and alkenes. This redox-neutral hydrocarboxylation proceeds in highyields across diverse functionalized alkene substrates with excellent regioselectivity. This operationally simple procedure can be readily scaled in batch at low photocatalyst loading (0.01% photocatalyst). Furthermore, this new reaction can
Organophotoredox assisted cyanation of bromoarenes <i>via</i> silyl-radical-mediated bromine abstraction
作者:Maniklal Shee、Sk. Sheriff Shah、N. D. Pradeep Singh
DOI:10.1039/d0cc00163e
日期:——
The insertion of a nitrile (–CN) group into arenes through the direct functionalization of the C(sp2)–Br bond is a challenging reaction. Herein, we report an organophotoredox method for the cyanation of aryl bromides using the organic photoredox catalyst 4CzIPN and tosyl cyanide (TsCN) as the nitrile source. A photogenerated silyl radical, via a single electron transfer (SET) mechanism, was employed
2,4,5,6-Tetrakis(3,6-di-tert-butyl-9H-carbazol-9-yl)isophthalonitrile (4CzIPN-tBu) was developed as a photocatalyst for the phosphorus-radical-initiated cascade cyclization reaction of isocyanides. By using 4CzIPN-tBu as catalyst, we developed a visible-light-induced proton-coupled electron transfer strategy for the generation of phosphorus-centered radicals, via which a wide range of phosphorylated