Studies On The Synthesis Of Polysubstituted Dihydropyrrole And Pyrrole Compounds

Pyrrole is nitrogen-containing five-membered heterocyclic compound and widely distributed of natural and non-natural compounds.These compounds usually possess a broad spectrum of biological activities such as anti-infammatory,antiviral,anti-tumor,antifungal,and antibacterial activities etc.Besides their biological activity,pyrrole compounds have also been applied in materials science areas such as dyes,conducting polymers and organic semiconductors etc.In view of the important application of pyrrole structural units in pharmaceutical chemistry and materials science.Therefore,new strategies and methods for the synthesis of pyrrole and its derivatives have attracted much attention of synthetic chemists.In this paper,based on our team’s long-term research on the chemical properties of thiane,we developed an effective method without transition metal catalysis to synthesize pyrroles,which is mainly divided into the following two parts:Chapter 1.A review of pyrrole compoundsThe physical and chemical properties of pyrrole compounds and their applications in biology are briefly introduced,and the synthetic methods of pyrrole compounds that have been reported at present are summarized.Chapter 2.Research on the Dithiane-Induced [3+2] Cycloaddition Tactic for the Convergent Synthesis of Dihydropyrrole and Pyrrole DerivativesBased on the convergence strategy and the efficient synthesis of pyrrole,we select β-chlorovinyl-1,3-dithiane and a variety of imines to synthesize substituted dihydropyrrole and pyrrole compounds through [3+2] cyclization.Usingβ-chlorovinyl-1,3-dithiane to form 1,3-dipoles under the action of potassium tert-butoxide,the addition reaction of imines is carried out.Using this method,we obtained 45 pyrrole derivatives with moderate to good yields,including combretastatin A-4 and COX-2 selective inhibitor pyrrole derivatives etc.The method has the characteristics of mild reaction conditions,short reaction time,good functional group tolerance,without transition metal catalysis and gram-scale conversion with good yield.