| Metal carbene species are an important class of intermediatesin organic synthesis and have been applied in many powerfulsynthetic methods.N-sulfonyl-1,2,3-triazole have recently received much attraction as efficient,safe,green precursors of ?-imino metal carbine.In general,N-sulfonyl-1,2,3-triazole can be efficiently intercepted by transition-metal catalysts(such as Rhodium(II)catalysts,Nickel(0)catalyst)to give rise to highly reactive rhodium(II)azavinyl carbenes,which can undergo many typical carbenereactions,such as cyclopropanation,C-H,O-H or N-H insertion and other types of carbene-induced reactions.Our group had reported series work about N-sulfonyl-1,2,3-triazole.Base on our previous studieson N-sulfonyl-1,2,3-triazole,we developed atandem O-H insertion/[1,3]-alkyl shiftreactions betweenrhodium azavinyl carbenoids andbenzylic alcohols for synthsisof ?-aminoketones.The product can transform to tetrahydroisoquinolinesthrough Pictet-Spengler reactions.Whereas the replacement of thebenzylic alcohols with furfuralcohol,resulted in tandem O-H insertion/[3,3]-sigmatropic rearrangement reaction formation of ?-aminoketones,which contain furan.Meanwhile,we also study on the reaction of 1,3-diketones(the equivalents of enol)with 1-sulfonyl-1,2,3-triazoles.For acyclic 1,3-ketones undergo the O-H insertion to form 4-oxazoline intermediate and result in 2-acetyl pyrroles;whereas cyclic 1,3-diketones without functional group at C2 position chemoselectively afforded 2,3-fused pyrroles.If2-methylcyclohexane-1,3-dione,a simple keto-enol tautomerization takes place,resulting in?-aminoketone.The thesis has four chapters:In Chapter One,the development of the N-sulfonyl-1,2,3-triazole chemistry is reviewed.The thesis proposal is prescented in Chapter Two.Chapter Three show the reaction between N-sulfonyl-1,2,3-triazole and benzylic alcohols or furfuryl alcoholsChapter Four described the reaction between N-sulfonyl-1,2,3-triazole and1,3-diketones. |
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