Studies On The Synthesis And Application Of ?-alkenoylcyclobutenone

As the important kind of small ring compounds,cyclobutenone derivatives have been applied as a key component of various biologically active molecules or natural products.The compounds are also used as one of the important synthetic chips,which have been used to prepare a variety of large biologically active molecules and natural products due to its high selectivity of ring-opening reaction.Therefore,due to their biological activity and high reactivity,cyclobutenones and derivatives have attracted considerable attention.Over the years,the synthesis of various functionalized cyclobutenones and their applications have been reported widely,but there are a few reports on the synthesis of ?-alkenoylcyclobutenone.Thus,in this thesis we mainly studied the synthesis of ?-alkenoylcyclohexenone compounds and its application of ring-opening reaction.The results were as follows:A new strategy for the synthesis of a series of ?-alkenoylcyclobutenones has been developed by the reaction of 3-amino-cyclobutenones with various aldehydes in the presence of LDA.On this basis of reaction,a series of multi-substituted lactones were obtained by a sequential ring-opening reaction of ?-alkenoylcyclobutenones using Cu(OTf)2 as catalyst.With 3-aminocyclobutenone compound as the starting material,a series of fully substituted indole compounds were efficiently prepared via Cu-catalyzed opening-cyclization reactions of 3-amino-cyclobutenones with dimethyl butynedione.The reaction not only has the advantages of simple starting material,easy to operate and high yield,but also creates a new method for the preparation of fully substituted indole compounds from simple starting materials.