New Reactions For The Preparation Of 2-Sulfonylindoles And 3-Selanylindoles

Sulfur-containing and selenium-containing indoles are important hetero cyclic compounds and intermediates in organic synthesis.They are widely used in dyes,materials,pesticides,and pharmaceuticals.Based on its unique properties and potential values,scientists have developed many methods for synthesizing these containing sulfur and selenium group indoles.However,these methods are still have some limitations such as the use of expensive raw materials and transition metal catalysts,need of long reaction times and high reaction temperatures,and so on.Therefore,the development of the efficient,convenient,economical and environmentally friendly synthesis methods is still desired.This dissertation mainly introduces the new methods we have developed for the synthesis of sulfur-containing and selenium-containing indole compounds,which can be divided into four parts:1.Literature review.This section mainly introduces the biological activity of indole compounds containing sulfur and selenium groups and the progress in the synthesis of these compounds in recent years.2.Potassium iodide catalyzes the selective reaction of indole with sodium sulfinate.Using indole and sodium sulfinate as the substrate,potassium iodide as the catalyst and potassium persulfate as the oxidant,we successfully synthesized 2-sulfonyl indole compounds in water at room temperature,and also proposed the catalytic cycle mechanism.This regioselective 2-sulfonylation of indoles using water as solvent is an environmentally benign protocol,which has mild reaction conditions and simple procedure.3.Potassium iodide,bromide and chloride-catalyzed reaction of indoles with diselenides.In the presence of iodide and oxidant,the reaction of indoles with diselenids proceed smoothly to form 3-selenyl indole compounds.The reaction conditions were optimized and the catalytic cycle mechanism was hypothesized.The reaction is mild and efficient,providing a selective method for the synthesis of 3-selenyl indole compounds.Based on the basis of this chapter,we explored another way to synthesize 3-selenyl indoles.Using bromide or chloride as catalyst,m-chloroperoxybenzoic acid as the oxidant,the reaction of indoles with diselenides can be also carried out,affording a series of 3-selanylindoles with high regioselectivity and in good yields.This method has greener characteristic and enriches the methods for the synthesis of 3-selenyl indoles.