Studies On ATRA Of Perfluroroalkyl Halides With 1,n-Enynes By Photoredox Catalysis

Introduction of fluorine-containing groups into the molecule usually improves its lipophilic or metabolic stability,so fluorined compounds are widely used in medicine,pesticides and materials.In recent years,the synthesis and conversion of fluorine-containing molecules has become a hot topic in the field of organic synthesis.It is worth mentioning that the construction of novel and potentially bioactive polyfluoroalkylated heterocyclic molecules by green,efficient and photoredox means has also attracted more attention from synthetic chemists.1,n-enyne is a class of highly reactive molecules containing the C=C bond and C?C bond,and are often used in tandem radical reactions to construct some novel heterocyclic molecules.Based on our research group's interest in the novel synthesis and transformation of fluorine-containing molecules.The ATRA?atom transfer free radical addition?reaction of 1,n-enyne with polyfluoroalkyl halide was studied in this thesis.Two types reactions of 1,6-enyne and 1,7-enyne with polyfluoroalkyl halide ATRA by visible-light photoredox catalysis were developed,and several novel polyfluoroalkyl heterocycles were synthesized.The main content of this thesis is as follows:In the first part,a review has been made of the advances in the cyclization reactions involving different types of 1,n-enynes in recent years,as well as the reactive characteristics and applications of these compounds under some typical catalytic systems,including the application in the synthesis of polyfluorinated compounds.In the second part,a photoredox-catalyzed ATRA cyclization reaction of N-bridging 1,6-enyne with polyfluorinated halides was developed.Under the irridation of the 5 w LED blue light,using the relatively cheap,simple and abundant polyfluoroalkyl iodides/bromides as the source of fluoroalkyl radical source,fac-Ir?ppy?₃as the photosensitizer,1,6-distal radical ATRA addition of 1,6-enyne was realized through a economical and steoroselective way at room temperature,and more than 16 kinds of difuncationalized?halo-polyfluoroalkylation?tetrahydropyrroles were synthesized effectively.In the third part,a visible-light-induced ATRA reaction of 1,7-enyne with polyfluoroalkyl halide was developed to synthesize polyfluorined 2,4-dihydronquin olin-2?1H?-ones.Using cheap and simple polylfluoroalkyl iodides or bromides as the radical precursor,and fac-Ir?ppy?₃as the photocatalyst.,under the irradiation of 5w blue LED,different types of benzene-bridging 1,7-enyne containing variou s functional groups underwent tandem radical addition/cyclization,and 41 kinds of perfluorined 2,4-dihydronquinolin-2?1H?-ones with an external double bond were synthesized in high stereoselectivity?E/Z>99:1?and high efficiency.Nota bly,thearyl group in the terminal position of triple bond is replaced by a steric tert-butyl group,a divergent cyclization involving a hydrogen atom transfer?HAT?proce will take place,thereby leading to novel?,?-halo-perflfluorinated 2,4-dihy dronquinolin-2?1H?-onesIn the fourth part,in order insight into the ATRA reaction mechanism of 1,n-enyne and polyfluoroalkyl halides,several control experiments and fluorescence quenching experiments were carried out,and the possible reaction mechanism was proposed.At the same time,density functional calculation was used to verify the rationality of the proposed mechanism.