The Study Of Of Amidation And Trifluoromethylation By Decarboxylation

As an inexpensive and easily available compound, carboxylic acid has been studied wildly by researchers. A decarboxylation reaction with aryl carboxylic acid as substrate was reported recently, and the product is the same as the product of the Heck reaction. After the decarboxylation reaction has been reported, the use of transition metal as a catalyst for the decarboxylation coupling reaction has gradually attracted people’s interest and has become a hot research topic. In the synthesis of organic molecules with no planar structure, the transition metal catalyzed coupling reaction is of great significance. Therefore, the transition metal catalyzed decarboxylation reaction of alkyl carboxylic acids has been paid more and more attention by scientists.Photocatalytic coupling reactions have been widely concerned in recent years, the visible light photocatalytic reaction system also provides a new way for the decarboxylation reaction. Recently a lot of photocatalytic decarboxylation reactions have been reported. In the first chapter, we summarize the previous works from transition metal and photocatalytic decarboxylation reaction respectively.As the basic framework for the construction of the protein, the amide bond plays an important role in the life, and also exists in a variety of materials and drugs. At present,the most commonly used strategy is the acetylation of amines, although the most common method for the preparation of amides is through the condensation of carboxylic acids and amines. But the ideal strategy requires extremely harsh conditions, such as high temperature conditions, and in the process of the formation of amide bond, it is inevitable to pass the reaction of carboxylic acid ammonium salt. In the second chapter, we introduce a kind of Ag catalyzed decarboxylation of carboxylic acid. The reaction was carried out under air condition and the reaction conditions were mild. The yield of the reaction is good, and it shows excellent functional group tolerance. Moreover, when the amine of the substrate is replaced with a two amine compound, the product of a heterocyclic compound, such as benzimidazole, can be further obtained.Drug molecules containing CF3 can effectively improve their lipophilicity,absorbability and metabolic stability. Therefore, the introduction of CF3 into organic molecules has attracted much attention. There are many reports on the introduction of CF3 into organic molecules. However, the introduction of -CF3 to C (sp3) was significantly less studied than C (sp2) and C (sp). Recently in this field with alkyl halides, alkyl silane, alkynes and alkyl borate as the substrates of trifluoromethylation reaction have been reported. Recently, the transition metal catalyzed trifluoromethylation has been developed rapidly. Among them, Cu as a cheap and high activity catalyst can achieve a variety of trifluoromethylation. In the third chapter,we have developed an effective method for the realization of a-trifluoroacetophenone by the decarboxylation of β-keto acid. This reaction can be carried out at room temperature using Cu salt as a transition metal catalyst,and the yield of the product is good. In addition, the decarboxylation reaction system has good compatibility, many of the electronic and electronic substrates are able to participate in the reaction gotting the corresponding a-trifluoroacetophenone.