Cross-Coupling Reaction Of Benzylic Halides With Allyltributylstannane Catalyzed By Cu(OTf)₂

Transition metal-catalyzed Stille coupling reaction emerged as extremely powerful tools for the construction of carbon-carbon bond. The popularity associated with this reaction stemed from its good tolerance of many functional groups, high stereoselectivity, mild reaction conditions, high yields and so on. It has been applied industrially to the production of compounds such as natural products, polymers, functional materials, drugs and biological activity compounds.In this paper, the coupling reaction of benzylic halides with allyltributylstannane was investigated. The main contents were summarized below:1. The coupling reaciton of 1-chloromethyl-4-methylnaphthalene with allyltributylstannane was initially studied for optimizing the reaction conditions. The effects of catalyst, the amount of allyltributylstannane and solvent on the yield of the coupling reaction were investigated. The corresponding coupling product was obtained in 76% yield in CH2CI2, in the presence of 10 mol% Cu(OTf)2,1.5 eq. allyltributylstanane at room temperature. Under the optimum conditions, the coupling reations of various benzylic halides with allyltributylstanne were performed, and the maximum yield was 93%.2. It was found that the reaction of a substrate bearing an electron-donating group on aromatic ring could be completed in a few minutes, whereas the reaction of a substrate having an electron-withdrawing group on aromatic ring required longer time.29f,29h and 29j were unknown compounds and their structures were confirmed by 1H NMR,13CNMR, IR and HRMS.