Decarboxylative Trifluoromethylation Of Cinnamic Acids And Synthesis Of Quinazoline Derivatives Under Electrochemical Conditions

The application of electrochemistry to the field of organic synthesis is a highly attractive organic synthetic strategy.The electron provided by the anode and cathode can act as a stoichiometric oxidizer and reducer,which can reduce the usage of chemical reagents and the generation of chemical wastes and is perfectly in line with the green chemistry concept.Many simple organic molecules are gradually being used in the field of electrochemical organic synthesis to prepare more valuable organic compounds.Electrochemical decarboxylative coupling reaction of cinnamic acid compounds can produce various unsaturated coupling products.The trifluoromethyl sulfinate is a commonly used trifluoromethylation reagent and is gradually being used in the field of electrochemical synthesis to prepare various trifluoromethylated products.In addition,the alcohols can participate in the electrochemical intermolecular oxidative cyclization reaction to synthesize the organic compounds with complex skeletons.In this paper,we reviewed the related works and reported two electrochemical reactions:(1)the synthesis of 3,3,3-trifluoropropene derivatives via electrochemical decarboxylative coupling of cinnamic acid compounds with sodium trifluoromethylsulfinate;(2)the synthesis of quinazoline derivatives via electrochemical intermolecular oxidative cyclization of alcohol compounds,2-aminobenzophenone and ammonium acetate.In the second chapter,we introduced the research progresses of the preparation of 3,3,3-trifluoropropene derivatives via the decarboxylation coupling reaction of cinnamic acid compounds and sodium trifluoromethylsulfinate under non-electrochemical conditions.We also reported our work on the synthesis of 3,3,3-trifluoropropene derivatives via electrochemical decarboxylative coupling of cinnamic acid compounds and sodium trifluoromethylsulfinate.The optimal reaction conditions were determined by screening different solvents,additives,electrolytes,electrode materials and current.This method refrained from using catalysts and external oxidants,and was an environmentally friendly synthetic strategy.A wide range of cinnamic acids,either bearing electron-rich groups or electron-deficient groups on the phenyl rings were suitable for the reaction,while heteroaromatic substrates could also be transformed accordingly and attained corresponding products.In this chapter,the reaction mechanism is also studied in detail and a free radical reaction mechanism was proposed.In the third chapter,the research progresses of the synthesis of quinazoline derivatives involving 2-aminophenyl ketones in the past 20 years were reviewed.Based on the experiences of our group in the electrochemical synthesis of 2-substituted benzazoles and quinazolinone derivatives using alcohols,we designed a new synthetic method of quinazoline derivatives: three-component cyclization of alcohols,2-aminobenzophenone and ammonium acetate under electrochemical conditions.The optimal conditions for this conversion were determined by the variable-controlling approach,and the applicability of alcohol substrates was also preliminarily explored.