Study Of The C-C Bond Formation With N-heterocyclic Via Minisci Reaction

In nature,C-C bonds are found in a wide range of natural products,medical drugs and organic materials.With the continuous development of organic synthetic chemistry,the construction of C-C bond is still one of the core topics of modern organic synthetic chemistry.As a unique way of forming C-C bonds,Minisci reaction has developed into an important way of constructing C(sp2)-C(sp3)bonds.Traditional methods of constructing C-C bonds generally use metal catalysis.However,in the face of increasing attention to ecological environment,how to use metal-free,greener and more effective methods to construct C-C bond has become a hot topic for many organic chemists.In this paper,the formation of C-C bond was developed via the activation of the special N-heterocyclic based on Minisci reaction.Eventually,it is expected to expand the variety of medical drugs or simplify the existing synthesis methods of medical drugs.This paper mainly includes the following two aspects.The first part:the formation of ?-hydroxyalkyl radical by fatty alcohol under the action of ditert-butyl peroxide,and the further coupling reaction with 2-phenylimidazole[1,2-a]dipyridine successfully achieved the C(sp2)-C(sp3)bond construction.In this reaction,the environmentally friendly small molecule alcohols were used as not only reactants but also solvents,and functional groups were realized for the first time directly on the C-5 position of the 2-phenylimidazole[1,2-a]dipyridine.In addition,the system can also react with primary alcohols or secondary alcohols,and even extend to ether compounds such as 1,4-dioxane.One of the biggest advantages of this reaction is that it breaks through the previous limitation and achieves hydroxyalkylation directly at the C-5 position of 2-phenylimidazole[1,2-a]dipyridine for the first time.The second part:The methyl radicals generated by the peroxides DCP and TBHP under heating conditions were coupled with 2-phenylimidazole[1,2-a]dipyridine and quinoxalinone to construct the C(sp2)-C(sp3)bond.On the basis of achieving the methylation of the C-5 position of 2-phenylimidazole[1,2-a]dipyridine,the reaction can be further extended to another nitrogen heterocyclic compound,and the quinoxalinone can be more efficiently achieved the product of C-3 methylation under simpler conditions(mainly lower reaction time).Compared with previous reports using peroxides as methyl radical precursors to participate in the reaction,the conditions used in this method are greener,such as there is no metal catalyst,use acetic acid as solvent,etc.In summary,a series of derivatives of 2-phenylimidazole[1,2-a]dipyridine and quinoxalinone were synthesized by environmentally green chemical methods,which provided a new idea for the application of these two N-heterocyclic compounds in medicine or organic materials.In terms of synthesis,the main feature of this paper was a major breakthrough in selectivity of reaction sites and also developed of Minisci reaction.