Indirect electrochemical reductive cyclization of o-halophenylacrylamides mediated by phenanthrene†
3,4-Dihydroquinolone is an important drug and biological compound. o-Halophenylacrylamides were cyclized by two-electron reduction under electrochemical catalysis to obtain the corresponding 3,4-dihydroquinolinone products. This electrochemical cyclization improves the selectivity of the reaction when using phenanthrene as a reducing mediator. The mechanism study shows that phenanthrene has a good effect on the reaction, indicating that it is a good dielectric for electroreduction.