Selective electrochemical oxidation of tetrahydroquinolines to 3,4-dihydroquinolones

Abstract

We report an environmentally friendly electrochemical oxidation of tetrahydroquinolines to 3,4-dihydroquinolones. The reaction uses electricity as a "traceless" oxidant, O2 as a "green" oxygen source, and 2,2,6,6-tetramethylpiperidinooxy (TEMPO) as a...

Electrochemically enabled decyanative C(sp3)–H oxygenation of N-cyanomethylamines to formamides

“…Based on the above-described research results and previous reports, 5,6,8 a convincing electrocatalytic mechanism is presented in Scheme 4. First, the anodic single electron oxidation of tertiary amine 1 leads to the generation of nitrogen-centered radical cation I , which loses one proton H + quickly to furnish a carbon-centered radical II .…”

“…Electrochemical synthesis, which employs traceless electrons as clean and efficient redox reagents, is becoming increasingly popular to increase molecular complexity, 7 and gains prominent recognition in developing environmentally benign alternatives for oxidative C(sp 3 )–H oxygenation reactions at present. 8 In 2019, Deprez and co-workers developed an electrochemically driven aminoxyl-mediated selective Shono-type C(sp 3 )–H oxygenation of pyrrolidines to build pyrrolidinones. 8 g Very recently, He and co-workers described a valuable iodine-mediated electrochemical C(sp 3 )–H oxygenation of tetrahydroquinolines for the preparation of a series of 3,4-dihydro-quinolones in the presence of molecule O 2 (Scheme 1b).…”

Interfacial Micro‐Environment of Electrocatalysis and Its Applications for Organic Electro‐Oxidation Reaction

“…The library of IME for OEOR should be more enriched. Despite many progress have been achieved in recent years, exploration of its application potential toward other kinds of organics with rich functional groups and complicate structures (e.g., degradation of antibiotics, [194][195][196] synthesis of medicines including quinolines, [197] finerenone, [198] narural products, [199] and peptides, [65] and of fine chemicals like indole derivatives [67] ) is still highly desirable and necessary. Properties of these reactants vary vastly from polarity, chain length, and configuration, hydrophilicity and hydrophobicity, solubility to adsorption strength etc.…”

Electrochemical Synthesis of β-Iodoesters by 1,2-Iodoesterization of Unactivated Alkenes with Carboxylic Acids and Tetrabutylammonium Iodide

“…Organic electrosynthesis utilizes electric current as an inexpensive, renewable, and safe reagent to replace stoichiometric chemical oxidants or reductants, and the selectivity of the reaction can be tuned by changing the electrochemical conditions. Therefore, organic electrosynthesis has significant advantages such as high functional group tolerance, mild reaction conditions, environmental friendliness, and sustainability, making it one of the important methods for organic synthesis . Because of their abundance, alkenes provide an excellent starting point for organic electrosynthesis .…”