Direct Electrochemical Defluorinative Carboxylation of gem-Difluoroalkenes with Carbon Dioxide

Abstract

We report a facile and economical synthesis of α-fluoroacrylic acids via direct electrochemical defluorinative carboxylation of gem-difluoroalkenes with CO2. By using a platinum plate as the working cathode and a cheap nickel plate as the anode in a user-friendly undivided cell under constant current conditions, the reactions proceed smoothly under room temperature, without the use of expensive transition metal catalysts, ligands, external base or reductant, affording the desired adducts in up to 83% yield and 20:1 Z/E ratio, with good functional group tolerance. A cyclic voltammetry study was conducted and suggested a novel ECEC process.

Electroreductive Cross‐Coupling of Trifluoromethyl Alkenes and Redox Active Esters for the Synthesis of Gem‐Difluoroalkenes

“…The alkyl radical precursor 2 should be more easily reduced than (i) trifluoromethyl alkenes 1 [11] and (ii) gemdifluoroalkenes 3. [14] Moreover, (iii) the nucleophilic radical III generated near the cathode should react with 1 prior to its homocoupling. Herein, we wish to report a novel electrosynthesis of gem-difluoroalkenes through electroreductive carbofunctionalization of trifluoromethyl alkenes.…”

Photochemical and electrochemical strategies in C–F bond activation and functionalization

“…In 2020, Wu and Zhou's group reported another electrochemical defluorinative carboxylation of gem-difluoroalkenes with CO 2 for rapid access to valuable α-fluoroacrylic acids in good to excellent yields (Scheme 38). 54 The reaction proceeded under mild conditions using Ni (+) and Pt (−) as the anode and the cathode, respectively, with a wide substrate range and good functional group compatibility. The mechanism for the reaction of gem-difluoroalkenes with CO 2 is shown in Scheme 38.…”

Recent Advances in Catalytic Nonenzymatic Kinetic Resolution of Tertiary Alcohols

“…In 2020, Zhou, Wu and co-workers reported the Ag(I)-catalyzed KR of tertiary propargylic alcohols 113 based on an asymmetric carboxylative cyclization with chiral Schiff base 115 as the ligand (Scheme 20 ). 48 Besides the recovered chiral tertiary alcohols, these reactions also produced chiral cyclic carbonates 114 under very mild reaction conditions. However, this KR method gave the propargylic alcohols and cyclic carbonates in poor to moderate ee values with low selectivity factors ( s = 2–6).…”