Study On The Tandem Reaction Of Allenoate Or MBH Carbonate With Thioaurones

Domino reaction,all kinds of complex target molecules was constructed by extremely convenient methods.Because a large number of complex intermediates produced in the process of reaction does not need to be separated and purified,moreover,the reaction time and energy consumption are greatly reduced.So tandem reaction has attracted wide attention in the field of organic synthesis.In addition,allenoate is a kind of material with high reactivity and is an important intermediate for synthesis.It has been widely used in various domino reactions,so as to construct a variety of heterocyclic and carbocyclic compounds efficiently.Therefore,this paper will be based on phosphine catalyzed tandem reaction of allenoate to construct benzothiophene and carbon heterocyclic compounds efficiently,the main work is divided into the following aspects:1)A series of thioaurones analogs were synthesized from substituted thiophenol,and the[4+2]domino annulation was finished with allenoate under the catalysis of phosphine.In this reaction,γ-benzyl allenoate participates as a two-carbon synthon and benzothieno[3,2-b]pyran derivatives was synthesized.Moreover,the reaction has a good yield,so the step of the reaction has potential application value.2)On the basis of the above work,a series of raw materials containing active hydroxyl groups were synthesized by modifying the thioaurones analogs and reacted with the unsubstituted allenoate under the catalysis of phosphine to produce the benzothiophene-fused dioxabicyclo[3.3.1]nonane derivatives.The substrate of the reaction has good adaptability,and the target product can be produced with high yield under mild reaction conditions.Moreover,the structure of the target product exists in many natural products and has high utilization value.3)Based on the second series of raw materials,we found that the exchange of hydroxyl groups into protected amine groups also has research value.When reacted with MBH carbonate to form a benzothienobicyclo[4.3.0]nonane derivative.The reaction uses CH₃CN as a solvent,and the structure of the product may have strong biological activity.Therefore,the synthesis of benzothienobicyclo[4.3.0]nonane derivatives is very useful.A total of 120 new compounds were synthesized in this paper.All the compounds were determined by ¹H NMR,¹³C NMR,IR,HRMS,m.p.（solid）.The structure of the representative compounds was determined by X-ray single-crystal diffraction.