N-heterocyclic Carbene Catalysis Huisgen Cycloaddition

Among the numerous heterocyclic compounds, 1,2,3-Triazole is a very important class of compounds. Because it has a unique biological activity, 1,2,3-Triazole is widely used in the application of structural modification of polypeptides, DNA and sugar.The preparation of 1,2,3-Triazole compounds is the important way to Huisgen reaction.But the traditional heating mode, can make the addition reaction area such as poor selectivity and longer reaction time deficiency.Copper catalytic azide cycloaddition(CuAAC) of acetylene from was first reported in 2002, has quickly become a lot of research in the field of hot spots.Such as medicinal chemistry, material chemistry and other fields.CuAAC reaction to get attention because of its good stereoselectivity, functional group tolerance and modularity, etc.Microwave heating is a kind of molecular internal heating, compared with the traditional heating, microwave heating so that the temperature of the inside of the molecule does not exist in the gradient, so more efficient and rapid. In the context of the Huisgen reaction, the microwave assisted heating method has been applied to the Huisgen reaction, and has achieved good results. We made by single molecule with TMS of the alkyne and azide, by microwave radiation, intermolecular Huisgen reaction was completed the same copper exists without need to remove the protective silicon base, greatly reduce the reaction time and the yield is very high.With the development of various carving, Cu- NHC complex was also applied to Huisgen reaction.And achieved good experimental results. Our job is to further studies of Cu- NHC complex to fold the nitrogen compound with TMS protection at the end of the cycloaddition of acetylene catalytic effect, and using amide carbonylation catalyst for the first time.Systematic design of a series of the substrate, and the synthesis of macrocyclic.The results show that nitrogen impurity carving with amide carbonylation catalyst, it can obtain very good yield and very good stereoselectivity.Intermolecular addition reaction is mainly generated 1,4,5-trisubstituted triazoles of 1,2,3-Triazole compounds. And product are Triazole desilication.Very important, this is the first time amide as catalyst, and achieved very good catalytic effect, this method also need not in addition to acetylene silicon-based protection before reaction.We also use the experiment proved that the amide carbonylation reaction of desilication participate in important role.Enrich the click chemistry more than work, and for the synthesis of three azole nitrogen provides multiple methods.