Chiral Metal Salen Complexes as Chiral Electrocatalysts for Asymmetric Electrochemical Carboxylation of Acetophenone

Abstract

Asymmetric electrochemical carboxylation is the direct and effective method to fix and utilize CO₂, and the selection of chiral catalysts is crucial. In this paper, a series of chiral metal salen complexes are prepared as chiral catalysts to achieve enantioselective conversion of acetophenone with CO₂ to synthesis chiral 2‐hydroxy‐2‐phenylpropionic acid under electrochemical conditions. Under the catalysis of Ni^IIL1, the enantiomeric excess (ee) value of 90 % and yield of 59 % are obtained. By cyclic voltammetry and potentiostatic electrolysis, the effects of metal centers and tert‐butyl groups in ligand structures on the catalytic results are studied and the possible reaction mechanism is proposed.