Reaction between alkyl isocyanides and dialkyl acetylenedicarboxylates in the presence of N-alkyl isatins: convenient synthesis of γ-spiro-iminolactones

The highly reactive 1:1 intermediate generated in the reaction between an alkyl isocyanide and a dialkyl acetylenedicarboxylate is trapped by N-alkyl isatin to yield iminolactones in fairly high yields.     

Reaction between alkyl isocyanides and dialkyl acetylenedicarboxylates in the presence of benzoyl cyanides: one-pot synthesis of highly functionalized iminolactones

The highly reactive 1:1 adduct, produced from the reaction between dialkyl acetylenedicarboxylates and alkyl isocyanides, was trapped by benzoyl cyanide derivatives to afford dialkyl 5-alkylimino-2-cyano-2-aryl-2,5-dihydro-3,4-furandicarboxylates in fairly good yields.     

An efficient dealkylative addition of trialkylamines to dialkyl acetylenedicarboxylates in the presence of a metallic chloride

Dialkyl acetylenedicarboxylates react effectively with an array of trialkylamines in dioxane at 80 °C in the presence of a metallic chloride to afford the corresponding aminomaleates in good yields.     

Organocatalyzed enantioselective synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carboxylates

The organocatalyzed enantioselective synthesis of biologically active 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carboxylate derivatives was achieved using bifunctional cinchona alkaloids as the catalysts. Using quinine thiourea as the catalyst, the tandem Michael addition-cyclization reaction between 1,3-cyclohexanediones and alkylidenecyanoacetate derivatives gives the desired products in high yields (up to 92%) and good ee values (up to 82%).     

Reaction between isocyanides and dialkyl acetylenedicarboxylates in the presence of strong CH-acids: one-pot synthesis of highly functionalized annulated 4H-pyrans

The highly reactive 1:1 adduct, produced from the reaction between dialkyl acetylenedicarboxylates and alkyl isocyanides, was trapped by strong cyclic CH-acids such as 4-hydroxy-6-methyl-2H-pyran-2-one or 4-hydroxycoumarin to yield dialkyl 2-(alkylamino)-5-oxo-4H,5H-pyrano[3,2-c]chromene-3,4-dicarboxylates or dialkyl 7-methyl-2-(alkylamino)-5-oxo-4H,5H-pyrano[4,3-b]pyran-3,4-dicarboxylates in good yields at room temperature.     

Reaction between isocyanides and dialkyl acetylenedicarboxylates in the presence of 4,5-diphenyl-1,3-dihydro-2H-imidazol-2-one. One-pot synthesis of 5H-imidazo[2,1-b][1,3]oxazine derivatives

The reactive 1:1 intermediate produced in the reaction between alkyl or aryl isocyanides and dialkyl acetylenedicarboxylates was trapped by 4,5-diphenyl-1,3-dihydro-2H-imidazol-2-one to yield highly functionalized 2,3-diphenyl-5H-imidazo[2,1-b][1,3]oxazine derivatives in fairly good yields.     

Five-membered 2,3-dioxo heterocycles: LXXVI. Reaction of methyl 1-aryl-3-benzoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates with 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione

Methyl 1-aryl-3-benzoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione to give methyl 11-aryl-12-benzoyl-9-hydroxy-4,6-dimethyl-3,5,10-trioxo-4,6,8,11-tetraazatricyclo[7.2.1.0^2,7]dodec-2(7)-ene-1-carboxylates which underwent thermal recyclization to 1-aryl-3-benzoyl-4-hydroxy-1′,3′-dimethylspiro[pyrrole-2,5′-pyrrolo[2,3-d]pyrimidine]-2′,4′,5,6′(1H,1′H,3′H,7′H)-tetraones.     

Efficient synthesis of methyl 4-chloro-6-fluoro-3-formyl-2H-chromene-2-carboxylate and its derivatives

Abstract  

Methyl 4-chloro-6-fluoro-3-formyl-2H-chromene-2-carboxylate was synthesized conveniently using Vilsmeier reagent. A series of new 2H-chromenes was prepared in high yields by introducing a corresponding β-halovinylaldehyde into condensation and cyclization reactions with active methylene compounds.     

Studies with 1,3-diketones: A convenient synthesis of some tetrahydro-4H-benzopyran and tetrahydroquinoline derivatives

A facile, one-step synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-benzopyran derivatives 4a-e via cyclo-addition reactions of acrylonitrile derivatives 1a-e with 1,3-cyclohexandione 2 is described. On the other hand, the reactions of 2 with the thioamides 1f-h afforded 5-oxo-5,6,7,8-tetrahydroquinoline derivatives 9a-c in good yields. The structures of the prepared compounds were established from their elemental analyses, spectroscopic data, and by their chemical transformations. © 1996 John Wiley & Sons, Inc.     

Organocatalyzed synthesis of 2-amino-8-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitriles

2-Amino-8-oxo-tetrahydro-4H-chromene-3-carbonitriles were synthesized for the first time from a tandem Michael addition-cyclization reaction between cyclohexane-1,2-dione and benzylidenemalononitriles. An enantioselective synthesis of these compounds was achieved in moderate ee values (up to 63% ee) by using a cinchona alkaloid-derived thiourea catalyst.     

Reactions between isocyanides and dialkyl acetylenedicarboxylates in the presence of 1,2-diacylhydrazines. One-pot synthesis of highly functionalized pyrazoles

The reactive 1:1 intermediate produced in the reaction between isocyanides and dialkyl acetylenedicarboxylates was trapped with 1,2-diacylhydrazines to yield highly functionalized pyrazoles in good yields.     

A new convenient synthesis of trisubstituted 1,3-dioxole-4-carboxylates from methyl 2-diazo-3-oxobutyrate and aldehydes

The interaction between methyl 2-diazo-3-oxobutyrate and the carbonyl group of aliphatic, aromatic, and α,β-unsaturated aldehydes under bis(hexafluoroacetoacetonato)copper(II) catalysis furnishes 1,3-dioxole-4-carboxylates in preparatively useful yields. The apparent 1,3-dipolar cycloaddition reaction of the metal carbene complex is remarkably free of competing processes.     

Electrocatalytic multicomponent transformation of cyclic 1,3-diketones, isatins, and malononitrile: facile and convenient way to functionalized spirocyclic (5,6,7,8-tetrahydro-4H-chromene)-4,3′-oxindole system

An electrochemically induced catalytic multicomponent transformation of cyclic 1,3-diketones, isatins, and malononitrile in alcohols in an undivided cell in the presence of sodium bromide as an electrolyte results in the formation of spirooxindoles with fused functionalized 5,6,7,8-tetrahydro-4H-chromene system in 83-98% yields. The application of this efficient electrocatalytic method to the formation of medicinally relevant spirocyclic (4H-chromene)-4,3′-oxindoles is beneficial from the viewpoint of diversity-oriented large-scale processes and represents novel, facile, and environmentally benign synthetic concept for multicomponent reaction strategy.     

Formation of alkyl 1-methyl-3,9-dioxo-2-phenyl-2,3,4,9-tetrahydro-1H-pyrrolo[3,4-b]quinoline-1-carboxylates by thermolysis of alkyl 1,5-diaryl-4-methyl-2,3,6-trioxo-1,2,3,4,5,6-hexahydropyrrolo[3,4-b]pyrrole-4-carboxylates

Russian Journal of Organic Chemistry -     

Reaction of tert-butyl isocyanide and dialkyl acetylenedicarboxylates in the presence of 2-acetylbutyrolactone. Synthesis of functionalized α-methylene-γ-butyrolactones

Reaction of tert-butyl isocyanide with dialkyl acetylenedicarboxylates in the presence of 2-acetylbutyrolactone leads to the formation of dialkyl (E)-2-{(tert-butylamino)[2-oxo-4,5-dihydro-3(2H)-furanylidene]methyl}-2-butenedioates.     

The reaction of (N-isocyanimino)triphenylphosphorane with dialkyl acetylenedicarboxylates in the presence of 1,3-diphenyl-1,3-propanedione: a novel three-component reaction for the stereoselective synthesis of dialkyl (Z)-2-(5,7-diphenyl-1,3,4-oxadiazepin-2-yl)-2-butenedioates

Reactions of dialkyl acetylenedicarboxylates with (N-isocyanimino)triphenylphosphorane in the presence of 1,3-diphenyl-1,3-propanedione proceed smoothly at room temperature to afford dialkyl (Z)-2-(5,7-diphenyl-1,3,4-oxadiazepin-2-yl)-2-butenedioates in high yields. The stereochemistry of the final products were confirmed by single crystal X-ray structure determination. The reaction is completely stereoselective.     

无外加催化剂条件下2-氨基-3-腈基-4-芳基-7,7-二甲基-5-氧 代-4H-5,6,7,8- 四氢苯并-[b]-吡喃-3-羧酸乙酯的合成

亚苄基氰基乙酸乙酯(1)与5,5-二甲基-1,3-环已二酮在乙二醇中不加任何催化剂于80℃反应2～3h得2-氨基-4-芳基-7,7-二甲基-5-氧化-4H-5,6,7,8-四氢苯并-[b]-吡喃-3-羧酸乙酯(3),产率75%～93%。     

One-pot, three-component reaction of isocyanides, dialkyl acetylenedicarboxylates, and non-cyclic anhydrides: synthesis of 2,5-diaminofuran derivatives and dialkyl (E)-2-[(N-acyl-N-alkylamino)carbonyl]-2-butenedioates

Abstract  

Isocyanides, dialkyl acetylenedicarboxylates, and non-cyclic anhydrides, for example acetic anhydride or benzoic anhydride, react in one-pot to afford 2,5-diaminofuran derivatives and dialkyl (E)-2-[(N-acyl-N-alkylamino)carbonyl]-2-butenedioates in fairly good yields at room temperature.