The Synthesis Of Substituted 3-methylthiofuran Compounds And Pyrrolo[1,2-a]Quinoxaline Compounds

The pyrrolo[1,2-a]quinoxaline skeleton,as important N-heterocyclic compound,is often found in natural products and pharmacologically active molecules and exhibits broad pharmacological profile.At present,most of drug molecules,printing and dyeing materials,and photoelectric materials are composed of these organic heterocyclic compounds.Herein,the synthesis of heterocyclic compounds from available materials is significative.Several explorative researches for the construction of C-S,C-N and C-C bonds and the synthesis of heterocyclic compounds have been developed by our group.We disclosed some methods to synthesize 3-methylthiofurans and pyrrolo[1,2-a]quinoxaline derivatives,as shown in the following parts:Part?:Metal-free synthesis of 3-methylthiofurans from homopropargylic alcohols and DMSOSubstituted furans,as key heterocyclic compounds,play increasingly important roles in organic chemistry,drug discovery,and materials science.DMSO has been widely used as a common,cheap and aprotic polar solvent in organic synthesis.Furthermore,DMSO also can be utilized as methylthiolation agent in the C-S bond formation.Herein,we developed a direct method to form substituted methylthiofurans from homopropargylic alcohols and DMSO under metal free reaction conditions via tandem sulfenylation/cyclization reaction in one-pot manner.The reaction has good compatibility and high yields.Part?:Synthesis of fused B-containing heterocyclic compoundsWe have developed a metal-free method to synthesize fused substituted4,5-borazaropyrrolo[1,2-a]quinolineswith1-?2-aminophenyl?pyrrolesandpotassium organotrifluoroborates.Optical properties of some products were investigated by UV/Vis spectroscopy and spectrofluorometry.Part?:Synthesis of alkyl substituted pyrrolo[1,2-a]quinoxaline derivativesThe pyrrolo[1,2-a]quinoxaline skeleton,as important N-heterocyclic compound,attracts much attention because of their special physical and chemical properties,biological activity and pharmacological value.We disclosed a method to synthesize alkylol-pyrrolo[1,2-a]quinoxalines from 1-?2-aminophenyl?pyrroles and cyclic ethers via the FeCl₃-catalyzed and cleavage of cyclic ethers.At the same time,we developed a Cu-catalyzed method to form alkylnitrile substituted pyrrolo[1,2-a]quinoxalines from 1-?2-aminophenyl?pyrroles and cyclobutanone oxime through the cleavage of C-C bond and the construction of C-C and C-N bonds.These two procedures exhibit excellent compatibility and good yields.