Studies On The Cyclopropenes Involved In Povarov And Diels-Alder Reaction

This dissertation was concerned with cyclopropenes for Povarov reaction,which was applied in synthesis of dihydroquinolines,benzazepines and BODIPY fluorescent derivatives.Then four unnatural amino acids containing cyclopropene were synthesized and envaluated in Diels-Alder reaction.It consists of the following four parts:Firstly,unique reactivity of cyclopropenes was introduced.As the highly strained ring and low distortion energy,cyclopropene had been demonstrated to be important synthetic intermediates in organic chemistry,including cycloaddition reactions,ring-opening reactions,rearrangements and C-H bond activation and so on.Based on the activation-distortion model,the distortion energy of cyclopropenes is smaller than those of other olefins,resulted easily in cycloaddition and ring-opening reactions.In chapter 2,an efficient construction of cyclopropane-fused dihydroquinolines was established by a novel Povarov-type three-component reaction of cyclopropenes,aromatic aldehydes and anilines in the presence of trifluoromethanesulfonic acid.It is different from the general Povarov reaction,dihydroquinoline was mediated via hydrogen transfer reaction after Mannich addition and aromatic electrophilic addition process.Furthermore,the dihydroquinolines were smoothly converted to benzazepine derivatives via a ring opening followed by an isomerization sequence.There were 19dihydroquinolines and 8 benzazepines afforded with 57-96%,90-98%yield respectively.It is expected that the disclosed protocol will be applied broadly.In chapter 3,the research progress of BODIPY fluorescent was summarized.The products of Povarov reactions are very similar to N,N-chelating ligands,which constructed the backbone of BF₂ complexes.Therefore,8 new types of BODIPY derivatives were efficiently constructed and their optical properties were evaluated.The Suzuki coupling reaction was used to modify and enlarge the BODIPY derivatives compounds.It was measured that the maximum emission wavelength can reach 667 nm,and the highest fluorescence quantum yield and Stokes shift can be up to 40%and 211 nm.These compounds will be applied to the area of fluorescent probe molecules.In chapter 4,the development of protein modification was reviewed.In order to explore the reactivity between cyclopropene and tetrazine,four unnatural amino acids containing cyclopropene were synthesized.One of them is 23.5 times fast than norbornene in Diels-Alder reaction,which will be applied in the field of protein modification.As the main clue,the reaserch of cyclopropene for Povarov reaction was introduced in detail.Dihydroquinolines,benzazepines and BODIPY derivatives was synthesized smoothly.When the reactivity of cyclopropenes was envaluated in Diels-Alder reaction,it was detected that the cyclopropene is more fast than norbornene.