57699-28-2Relevant articles and documents
Unraveling two pathways for NHPI-mediated electrocatalytic oxidation reaction
Xu, Leitao,Yi, Yangjie,Hu, Sideng,Ye, Jiao,Hu, Aixi
, (2021/11/30)
Two pathways for N-hydroxyphthalimide (NHPI)-mediated electrocatalytic oxidation using phenylacetate derivatives as template substrates were first reported for benzylic C[sbnd]H oxidation to oxygenated and non-oxygenated products. DFT calculation indicates that the hydrogen-atom transfer (HAT) process between phthalimido-N-oxyl (PINO) and substrate is a rate-determined step. Aromatic α-keto esters and 2-((1,3-dioxoisoindolin-2-yl)oxy)-2-aryl acetate obtained by cross-coupling between benzylic radical and PINO can be selectively synthesized through controlling the concentration of PINO radical. This method provides a deep understanding for selective weak C[sbnd]H oxidation using NHPI as redox mediator.
Preparation method of alpha-ketoester compound
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Paragraph 0114-0117, (2021/04/21)
The invention discloses a preparation method of an alpha-ketone ester compound. The method specifically comprises the following operation steps: adding raw materials alpha-diazo ester and an organic photocatalyst into a reaction flask, then adding an organic solvent, and reacting for 2-12 hours in air at room temperature under the irradiation of a visible light lamp; after the reaction is monitored by thin-layer chromatography (TLC), stopping the reaction, and extracting a reaction solution by using ethyl acetate; concentrating the extracting solution under reduced pressure to obtain a crude product, and performing column chromatography separation on the crude product to obtain the alpha-diazonium ester compound. According to the preparation method, clean visible light is used as reaction energy, cheap organic dye is used as a photocatalyst, air is used as a green oxidizing agent and an oxygen source, and the preparation method has the advantages of simplicity and convenience in operation, no metal residue and mild reaction conditions.
Tandem Photoredox-Chiral Phosphoric Acid Catalyzed Radical-Radical Cross-Coupling for Enantioselective Synthesis of 3-Hydroxyoxindoles
Zhang, Yang,Ye, Dan,Shen, Lei,Liang, Kangjiang,Xia, Chengfeng
supporting information, p. 7112 - 7117 (2021/09/14)
A photochemical protocol that couples diarylamines and α-ketoesters to afford the chiral 3-hydroxyoxindoles through tandem photoredox and chiral phosphoric acid catalysis is developed. The reaction involves an enantioselective photochemical radical-radical cross-coupling process. The chiral phosphoric acid is discovered to play crucial roles by decreasing the reductive potentials of α-ketoesters and stereocontrolling the downstream asymmetric radical-radical cross-coupling via the formation of pentacoordinate complex.