Cobalt-Catalyzed Hydroxyperfluoroalkylation Of Alkenes

Fluoroalkylated organic compounds often have unique biological properties and are widely used in industrial chemicals,materials,agricultural chemicals and pharmaceuticals.In particular,the introduction of fluoroalkyl groups,due to their electron absorption and highly hydrophobic properties,often lead to great changes in their polarity,solubility,lipophilicity and metabolic stability.With the increasing demand for drug and pesticide development,there is great interest in the construction of fluorinated molecules.Some progress has been made in the reported perfluoroalkylation reactions in recent years,but the exploration of new methods that can take advantage of cheap catalysts and mild conditions as well as a wide range of substrates still needs to be explored.The perfluoroalkylation of olefin catalyzed by transition metal cobalt was studied in this thesis.This thesis mainly includes the following four aspects of work:1.A cobalt-catalyzed hydroxylperfluoroalkylation of olefin has been developed.In this reaction,styrene was used as the substrate,perfluorohexyl bromide was used as the source of fluoroalkyl,and cobalt tetrafluoroborate hexahydrate was used as the catalyst to obtain β-fluoroalkyl alcohols.2.The temperature,catalyst,time,solvent and other factors affecting the reaction were optimized to obtain the best reaction conditions.3.The substrate scope was investigated.Many alkenes can show good substrate tolerance.Aliphatic alkenes and aryl alkenes with natural product active structure are also suitable,and the resulting products can undergo different types of subsequent transformation.4.To explore the reaction mechanism,a possible free radical reaction mechanism is proposed.In conclusion,we have developed a highly efficient cobalt-catalyzed hydroxyl perfluoroalkylation of alkenes with a wide range of substrates and functional group tolerance.The method has good yield and mild conditions,and is tolerant to mono-,di-and tri substituted alkenes(including styrene and unactive alkenes).This strategy provides a valuable solution for the rapid and efficient construction of β-fluoroalkyl alcohols using cheap fluoroalkyl bromine.