The one-pot eight-component reaction between Meldrum's acid, an aromatic aldehyde, and an aryl amine was achieved in the presence of citric acid catalyst. The corresponding dispirohydroquinolines were obtained in ...The one-pot eight-component reaction between Meldrum's acid, an aromatic aldehyde, and an aryl amine was achieved in the presence of citric acid catalyst. The corresponding dispirohydroquinolines were obtained in good yields with excellent diastereoselectivity. This method is a combination of the Knoevenagel and Michael reactions.展开更多
A facile solid phase synthesis of 2-substituted 1,3-oxazin-6-ones using polymer-supported Meldrums acid has been reported. Reaction of the resin-bound cyclic malonic acid ester with triethyl orthoformate and subsequen...A facile solid phase synthesis of 2-substituted 1,3-oxazin-6-ones using polymer-supported Meldrums acid has been reported. Reaction of the resin-bound cyclic malonic acid ester with triethyl orthoformate and subsequent dou-ble substitution with amide, afforded the corresponding polymer-supported acylaminomethylene cyclic malonic acid ester, which upon thermal treatment led to 1, 3-oxazin-6-ones in good yields and with high purity.展开更多
An efficient ultrasound-assisted preparation of a series of novel 4-aryl-3-methyl-4,5-dihydro-l//-pyrazolo[34-b]pyridin-6（7H）ones via the reaction of 5-amino-3-methyl-1H-pyrazole,Meldrum＇s acid and various arylalde...An efficient ultrasound-assisted preparation of a series of novel 4-aryl-3-methyl-4,5-dihydro-l//-pyrazolo[34-b]pyridin-6（7H）ones via the reaction of 5-amino-3-methyl-1H-pyrazole,Meldrum＇s acid and various arylaldehydes using one-pot three-component approach is described.This rapid method produced the products in short reaction times（3-4 min） and excellent yields（87-95%）.展开更多
A series of novel Meldrum＇s acid C60 derivatives were prepared in moderate yields from a convenient one-pot reaction of C60, the Meldrum＇s acid derivatives, 12 and 1,8-diazabicyclo-[5,4,0]-undec-7-ene （DBU） in tol...A series of novel Meldrum＇s acid C60 derivatives were prepared in moderate yields from a convenient one-pot reaction of C60, the Meldrum＇s acid derivatives, 12 and 1,8-diazabicyclo-[5,4,0]-undec-7-ene （DBU） in toluene at room temperature under nitrogen atmosphere. All the new compounds were fully characterized by the spectral data and elemental analysis. A carbene intermediate mechanism was proposed for this reaction.展开更多
The three-component reaction of triphenylphosphine,dimethyl hex-2-en-4-ynedioate and arylidene N,N’-dimethylbarbituric acids in dry methylene dichloride at room temperature afforded trans-1,3-disubstituted 7,9-diazas...The three-component reaction of triphenylphosphine,dimethyl hex-2-en-4-ynedioate and arylidene N,N’-dimethylbarbituric acids in dry methylene dichloride at room temperature afforded trans-1,3-disubstituted 7,9-diazaspiro[4.5]dec-1-enes in good yields and with high diastereoselectivity.However,the similar three-component reaction with arylidene Meldrum acids resulted in a mixtures of cis/trans-1,2-disubstituted 7,9-dioxaspiro[4.5]dec-1-enes.Additionally,the three-component reaction of triphenylphosphine,dimethyl but-2-ynedioate and arylidene Meldrum acids gave polysubstituted 5-(triphe nyl-λ~5-phosphanylidene)cyclopenta-1,3-die nes.A plausible reaction mechanism was proposed for the formation of various products with different regioselectivity and diastereoselectivity.展开更多
A Rh(Ⅰ)-catalyzed highly regio-and enantioselective allylic alkylation of Meldrum acid with racemic allylic substrates bearing alkyl groups has been developed.The applying of chiral bisoxazopinephosphine ligand is es...A Rh(Ⅰ)-catalyzed highly regio-and enantioselective allylic alkylation of Meldrum acid with racemic allylic substrates bearing alkyl groups has been developed.The applying of chiral bisoxazopinephosphine ligand is essential for the high yields and selectivities.This method provides a rapid access to various chiral β-alkyl-γ,δ-unsaturated carboxylic acids and their derivatives.展开更多
基金the funding support received for this project from the Research Council of the University of Sistan and Baluchestanpartially supported by FEDER funding, the Spanish Ministerio de Economía y Competitividad MAT2006–01997,MAT2010-15094 and the Factoría de Cristalización(Consolider Ingenio 2010)
文摘The one-pot eight-component reaction between Meldrum's acid, an aromatic aldehyde, and an aryl amine was achieved in the presence of citric acid catalyst. The corresponding dispirohydroquinolines were obtained in good yields with excellent diastereoselectivity. This method is a combination of the Knoevenagel and Michael reactions.
基金Project supported by the National Natural Science Foundation of China (No. 20072032).
文摘A facile solid phase synthesis of 2-substituted 1,3-oxazin-6-ones using polymer-supported Meldrums acid has been reported. Reaction of the resin-bound cyclic malonic acid ester with triethyl orthoformate and subsequent dou-ble substitution with amide, afforded the corresponding polymer-supported acylaminomethylene cyclic malonic acid ester, which upon thermal treatment led to 1, 3-oxazin-6-ones in good yields and with high purity.
基金Financial support from the Research Council of University of Guilan is sincerely acknowledged
文摘An efficient ultrasound-assisted preparation of a series of novel 4-aryl-3-methyl-4,5-dihydro-l//-pyrazolo[34-b]pyridin-6（7H）ones via the reaction of 5-amino-3-methyl-1H-pyrazole,Meldrum＇s acid and various arylaldehydes using one-pot three-component approach is described.This rapid method produced the products in short reaction times（3-4 min） and excellent yields（87-95%）.
基金Project supported by the National Natural Science Foundation of China （No. 20532040）.
文摘A series of novel Meldrum＇s acid C60 derivatives were prepared in moderate yields from a convenient one-pot reaction of C60, the Meldrum＇s acid derivatives, 12 and 1,8-diazabicyclo-[5,4,0]-undec-7-ene （DBU） in toluene at room temperature under nitrogen atmosphere. All the new compounds were fully characterized by the spectral data and elemental analysis. A carbene intermediate mechanism was proposed for this reaction.
基金financially supported by the National Natural Science Foundation of China(No.21572196)the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘The three-component reaction of triphenylphosphine,dimethyl hex-2-en-4-ynedioate and arylidene N,N’-dimethylbarbituric acids in dry methylene dichloride at room temperature afforded trans-1,3-disubstituted 7,9-diazaspiro[4.5]dec-1-enes in good yields and with high diastereoselectivity.However,the similar three-component reaction with arylidene Meldrum acids resulted in a mixtures of cis/trans-1,2-disubstituted 7,9-dioxaspiro[4.5]dec-1-enes.Additionally,the three-component reaction of triphenylphosphine,dimethyl but-2-ynedioate and arylidene Meldrum acids gave polysubstituted 5-(triphe nyl-λ~5-phosphanylidene)cyclopenta-1,3-die nes.A plausible reaction mechanism was proposed for the formation of various products with different regioselectivity and diastereoselectivity.
基金financially supported by the National Natural Science Foundation of China(NSFC,Nos.21602130 and 21961023)the startup funding from Shanghai Jiao Tong University.
文摘A Rh(Ⅰ)-catalyzed highly regio-and enantioselective allylic alkylation of Meldrum acid with racemic allylic substrates bearing alkyl groups has been developed.The applying of chiral bisoxazopinephosphine ligand is essential for the high yields and selectivities.This method provides a rapid access to various chiral β-alkyl-γ,δ-unsaturated carboxylic acids and their derivatives.
