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The high selectivity of alkynes achieved by Dalian Chemical Institute for one-step preparation of bistin substituted olefins
[ Instrument network instrument research and development ] 1,2-bis-tin substituted olefins can be converted into olefins containing multiple functional groups through Stille coupling reaction, which is widely used in the fields of drug synthesis and complex molecular construction. At present, ditinization of alkynes is a way to prepare ditin substituted olefins. Traditional catalytic systems have problems such as narrow substrate range, expensive raw materials, poor spatial or chemical selectivity, and poor stability. Single-atom-site Catalysts (SASCs) have been widely used in the fields of electrochemistry and organic synthesis. However, most of them focus on the regularity of metal atoms and ignore the role of ligands and carriers.
Recently, the team of Ding Yunjie, a researcher at the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, and Pan Yingming, a professor at Guangxi Normal University, have collaborated to design and synthesize a series of porous organic polymers with triphenylphosphine as the framework for the ditin addition reaction of alkynes. Single-atom site heterogeneous catalyst to achieve high selectivity of alkynes to prepare ditin substituted olefins in one step.
Based on the reaction mechanism, the research designed and synthesized the palladium-based single-atom site catalyst to solve the related problems of the traditional catalytic system. The single-atom site catalyst can use low-priced reaction substrates, and can produce ditin substituted olefins in one step with high selectivity and high activity. The reaction yield is as high as 89%, the TON value is 770, and the ratio of ditin and monotin products It is about 100:1, which is suitable for the addition of more than 20 kinds of terminal alkynes with double tin, and the experimental results far exceed the catalyst performance reported in the literature. In addition, the catalyst utilizes a ligand exchange method to make the metal active sites reach a stable coordination environment and effectively avoid the agglomeration of metal atoms. This study shows that single-atom site catalysts not only provide an effective platform for the transformation of homogeneous catalysis into heterogeneous catalysis, but also have potential in developing new synthetic reactions and solving the problems of homogeneous catalysis.
Related results were published on Chem. The research work was funded by the National Natural Science Foundation of China and Guangxi Natural Science Foundation of China.