A new strategy of "bifunctional rhodium catalyst decarbonylation under visible light induction"

Recently, the team of Chen Qingan, a researcher at the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, has made progress in the study of visible light-induced imide decarbonylation under mild conditions, and developed a new strategy of "bifunctional rhodium catalyst decarbonylation under visible light induction". The decarburization of amide compounds under mild (30-40°C) conditions and the addition reaction with alkynes.

In recent years, since simple and readily available substrates can be converted into high value-added products with physiological or pharmacological activity in an efficient manner, research on inert bond activation catalyzed by transition metals has attracted much attention. Among the many inert bonds, the activation of amide bonds, which constitute the basic backbone of polypeptides, has always been a research hotspot. The transition metal-catalyzed amide decarburization reaction can directly modify amide-containing compounds and convert a wide range of amide-containing substrates into high value-added products. However, in the process of catalytic decarburization, the feedback bond between the π* orbital of carbon monoxide and the metal d orbital restricts the dissociation of the carbonyl metal. The currently developed metal-catalyzed decarbonylation reaction is dominated by heat-induced carbonyl dissociation, and the efficiency is generally low and the reaction conditions are harsh. Metal-catalyzed decarburization under mild conditions is one of the problems.

Chen Qing’an’s team developed a visible light-induced carbonyl rhodium intermediate based on the research of cobalt-catalyzed amide decarbonylation and transition metal-catalyzed alkyne and olefin resource utilization. The carbonyl dissociation and the addition of alkyne under mild conditions Reaction, and use this reaction to synthesize a series of polysubstituted isoquinolinone compounds. Studies have found that the quinoline-oriented acyl rhodium intermediate not only serves as a catalyst center, but also has the ability to absorb visible light. Under the excitation of visible light, the intermediate becomes an excited state, and the electrons in the feedback bond orbital are excited into the non-bonded orbital, which reduces the dissociation energy of the carbonyl group, thereby promoting the dissociation of the carbonyl group. This research has reference significance for realizing the conversion of carbonyl compounds under mild conditions.

Related results were published in "Germany Applied Chemistry". The research was funded by the National Natural Science Foundation of China, the China Postdoctoral Science Foundation and the "Xing Liao Talents" program.

Source: Dalian Institute of Chemical Physics