Study On The Synthesis Of 2-Aminoquinoline/3-Aryl-1H-Indole Compounds From 2-Vinylanilines

Nitrogen-containing heterocyclic compounds widely exist in nature,among them which quinoline and indole compounds are two common types of heterocyclic compounds,which have significant physiological and pharmacological activities,and is widely used in medicine,pesticides,materials,and organic synthesis.Therefore,the synthesis of quinoline and indole compounds has always been one of the hot spots in the field of synthetic chemistryIn this thesis,based on a brief review of the synthesis of N-heterocyclic compounds using 2-vinylanilines as starting material,we designed and explored the highly selective reaction of 2-vinylanilines and isothiocyanate promoted by K₃PO₄;the self-cyclization reaction of 2-vinylanilines oxidation by SeO₂,and the intermolecular cyclization reaction of 2-vinylanilines and isonitrile to synthesize a variety of 2-aminoquinoline and 3-arylindole derivatives.These methodologies have the characteristics of simple operation,high efficiency,and good selectivity.The feasibility of these new strategies is further proved by the gram-grade reaction.The main contents of this thesis are as follows:In the first chapter,based on the importance of quinolines and indoles,the progress in the synthesis of these compounds from 2-vinylanilines is summarized,and the background and significance were further discussed in this chapter.In the second chapter,the cyclization of 2-vinylanilines and alkyl/aryl isothiocyanate promoted by K₃PO₄ was realized.A series of 2-aminoquinoline compounds were synthesized with mild reaction conditions,excellent chemical selectivity,and a wide range of substrates.The metal-free method provides a new way for the synthesis of quinoline rings.In the third chapter,the intramolecular cyclization of 2-vinylanilines were achieved by using SeO₂ as an oxidant,and 3-aryl-1H-indoles were obtained in moderate to good yields.The amines of 2-vinylaniline substrates were unprotected,and reacts under relatively mild conditions and produce Se that could be recovered.This strategy has the advantages of simple operation and good functional group tolerance.In the fourth chapter,a series of 2-aminoquinolines in good to excellentyields were afforded in a direct,facile,and efficient approach by Se-catalyzed isonitrile and 2-vinylanilines under the air atmosphere.This reaction not used only low toxicity Se as the catalyst,but also a new C?sp²?-C?sp²?bond and C?sp²?-N bond were constructed by a one-step reaction.Both aliphatic and aromatic isonitriles were found to be suitable for this reaction.The above product structures were further characterized by ¹H NMR,¹³C NMR,and HRMS.Representative compounds of the partial structure were confirmed by X-Ray.