Research On A New Method Of Synthesizing Fluorine-containing Nitrogen And Oxygen Heterocyclic Compounds Through The HAS Process

In recent years,the synthesis of heterocyclic compounds by the homogenized aromatic ring substitution(HAS)process has received increasing attention from scientists.This conversion provides a good method for constructing new carbon-carbon and carbon-heteroatom bonds.The visible light catalytic oxidation-reduction reaction has gradually become one of the research hotspots due to its characteristics of green and high efficiency.The visible light catalyzed redox reaction can be used to efficiently synthesize some heterocyclic compounds through the HAS process.The paper introduces the methods of synthesizing different heterocyclic compounds by HAS process in recent years.On this basis,the synthesis of fluorine-containing heterocyclic compounds by two different methods was developed by visible light catalyzed tandem cyclization.The main contents of the thesis include the following two aspects:1.Photoredox-catalyzed cascade addition/cyclization of N-propargyl aromatic amines:access to 3-difluoroacetylated or 3-fluoroacetylated quinolinesA method for synthesizing fluorinated quinoline compounds using a propargyl arylamine with a fluorine-containing bromoester under visible light catalyzed radical tandem cyclization was developed.The reaction condition is mild and the suitability of the substrate is also relatively broad.The propargylarylamines with different substituent groups on the benzene ring can be reacted well to obtain a medium to good yield of the product.Through mechanism studies,the reaction may undergo a dehydroaromatization process.2.Synthesis of 6-fluoroalkyl 6H-benzo[c]chromenes via visible-light-promoted radical addition/cyclization of biaryl vinyl ethersThe brominated fluorine-containing reagent generates a fluoromethyl radical under visible light catalyst,and it is added with diaryl vinyl ether to synthesize 6-fluoroalkyl 6H-benzo[c]chromenes by tandem cyclization.The compatibility of the substrate of the method is relatively good,and different substituents on the aromatic ring can be retained.Further,the diarylvinyl sulfides can also be subjected to a series-forming ring reaction to synthesize sulfur-containing heterocyclic compounds.