Study On Copper-Catalyzed C_sp3-O Cross-Coupling Of Unactivated Alkyl Halides With Organic Peroxides

Aryl-alkyl esters present a class of useful organic building blocks, which have been utilized as solvents, lubricants, pesticides, spices and pharmaceutical sciences fields. Many efforts have been devoted to the study of the production of aryl-alkyl esters. In general, aryl alkyl esters were prepared by the following methods:alcohol and acid, alcohol and acryl halide, alcohol and acid anhydride and ether and the reaction of acryl halide. In recent years, Peroxide-participated Csp3-O bond formation reactions by breaking O-O bond are becoming very useful in modern organic synthesis. In terms of aryl alkyl ester synthesis, the reactions of organic peroxide with alkyl aldehyde, ketone have had much progress, and by reacting with alkylamine, alkyl alcohols and triethylaluminum, organic peroxides can also produce the aryl-alkyl esters. Among those peroxides, benzoic peroxyanhydride is the most widely used, and continuing to explore the synthesis methods of organic peroxides-participated aryl alkyl esters in the present basic research is still of great theoretical and application value.According to the literature research, we explore copper-catalyzed cross-coupling of organic peroxides and alkyl halides using unactivated alkyl halides reagent as the source of the alkyl group. Many synthetically important functional groups were well-tolerated under the optimal conditions. The system is suitable for all kinds of different lengths, different halogen substituted alkyl halogenated hydrocarbon. In transition metal catalyzed coupling reactions, the secondary alkyl halides are more prone to eliminate response and less prone to take part in the coupling reaction. In recent years, only the few working is reported to make copper catalyze secondary alkyl halides to participate in, but this reaction system is suitable for secondary alkyl halides, and the yield is higher.On the basis of the research in this reaction, we further explored a plausible reaction mechanism for copper-catalyzed cross-coupling of organic peroxides and alkyl halides were proposed through investigating other relevant literature. According to a large number of literatures, most of the organic peroxide-participated reactions are occurring free radical mechanism, so we performed some control experiments to study the mechanism of this reaction. We added several free radical inhibitors to the reaction and found the yield of product did not reduce, rejecting the conventional free radical mechanism. As a result, we put forward a new kind of mechanism.