Electrochemical C(sp<sup>3</sup>)–H Lactonization of 2-Alkylbenzoic Acids toward Phthalides
Jee Eun Hong, Jisong Yoon, Woohyun Baek, Kyumin Kim, Jae‐Hwan Kwak, Yohan Park
Abstract
Herein, we report direct electrochemical C(sp3)–H lactonization of 2-alkylbenzoic acids toward phthalides. The reaction provides a wide substrate scope of 2-alkylbenzoic acids bearing primary to tertiary C(sp3)–H bonds by utilizing a graphite anode, dichloromethane (DCM) solvent, hexafluoroisopropanol (HFIP) cosolvent, and n-Bu4NClO4 electrolyte. Our synthetic approach offers a simple, intuitive, and atom-economical protocol to synthesize various phthalides (25 examples, up to 92% yield) and obtain other 5- and 6-membered lactones (10 examples, up to 83% yield).
Topics & Concepts
ChemistryYield (engineering)DichloromethaneElectrochemistryAnodeSolventElectrolyteSubstrate (aquarium)Medicinal chemistryCombinatorial chemistryOrganic chemistryElectrodePhysical chemistryMaterials scienceGeologyMetallurgyOceanographyRadical Photochemical ReactionsCatalytic C–H Functionalization MethodsOxidative Organic Chemistry Reactions