An efficient one-pot three-component synthesis of functionalized pyrimido[4,5-b]quinolines and indeno fused pyrido[2,3-d]pyrimidines in water

A simple, efficient, and high yielding one-pot protocol for the synthesis of pyrimido[4,5-b]quinolines and indeno[2′,1′:5,6]pyrido[2,3-d]pyrimidines has been developed by three-component domino coupling of 6-amino-1,3-dimethyluracil, aldehydes, and cyclic 1,3-diketones in ecofriendly solvent water promoted by PTSA. The protocol avoids the use of expensive catalysts, toxic solvents, and chromatographic separation. The generality and functional tolerance of this convergent and environmentally benign method is demonstrated.     

A one-pot three-component reactions for the synthesis of fully substituted spiro indeno[1,2-b]quinoxaline derivatives

An efficient and simple approach of the synthesis of some spiro indeno[1,2-b]quinoxalines via a one-pot three-component reaction of 11H-indeno[1,2-b]quinoxalin-11-one, pyrazolone, and malononitrile in the presence of Na₂CO₃ at 70 °C is reported. This reaction has shown to have high atom economy.     

Rapid and efficient synthesis of poly-substituted quinolines assisted by p-toluene sulphonic acid under solvent-free conditions: comparative study of microwave irradiation versus conventional heating

A rapid and efficient method for the preparation of various poly-substituted quinolines has been developed through the Friedl?nder condensation of 2-aminoarylketone or 2-aminoarylaldehyde with carbonyl compounds in the presence of p-toluene sulphonic acid, which was achieved by both microwave irradiation and conventional heating under solvent-free conditions.     

Ultrasound-promoted one-pot, three-component synthesis of spiro[indoline-3,1'-pyrazolo[1,2-b]phthalazine] derivatives

A series of 3'-aminospiro[indoline-3,1'-pyrazolo[1,2-b]phthalazine]-2,5',10'-trione derivatives have been synthesized by a one-pot three-component reaction of isatin, malononitrile or ethyl cyanoacetate and phthalhydrazide catalyzed by piperidine under ultrasound irradiation. For comparison the reactions were carried out under both conventional and ultrasonic conditions. In general, improvement in rates and yields were observed when the reactions were carried out under sonication compared with classical conditions.     

Efficient polymeric catalyst for one-pot synthesis of acenaphtho[1,2-b]pyrroles

Some new derivatives of acenaphtho[1,2-b]furans have been synthesized efficiently by one-pot reaction of (acenaphthylen-1-yloxy)trimethylsilane, various aldehydes, and isocyanides in the presence of silica-supported ionic liquid.     

Simple synthesis of 7H-phenaleno[1,2-b]furan-7-one derivatives by one-pot, three-component reactions

The reaction of alkyl isocyanides with various aldehydes and 3-hydroxy-1 H-phenalene-1-one is described. The protocol offers facile and efficient synthesis of biologically interesting 9-(alkyl or arylamino)-7 H-phenaleno[1,2- b]furan-7-one derivatives from readily available starting materials in high yields.     

室温下Cu掺杂的ZnO纳米粉末催化多组分一锅法合成完全取代的茚并[1,2-b]吡啶(英文)

Cu doped ZnO nanocrystalline powder(10 mol%) has been found to be an efficient catalyst for the one‐pot multi‐component synthesis of fully substituted new indeno[1,2‐b]pyridines through a com-bination of 1,3‐indandione, propiophenone or acetophenone derivatives, aromatic aldehydes, and ammonium acetate in ethanol/H2 O at room temperature. The methodology is mild, efficient and high to excellent yielding.     

An efficient synthesis of imidazo[2,1-b][1,3]thiazins via a one-pot,three-component and solvent-free reaction

A simple and eco-friendly method for the synthesis of novel imidazo[2,1-b][1,3]thiazin derivatives has been developed via the one-pot, three-component and solvent-free reaction of thiohydantoins, aromatic aldehyde and 5,5-dimethylcyclohexane-1,3-dione in the presence of catalytic amount of p-toluene sulfonic acid, in good and excellent yields.     

Microwave promoted diastereoselective synthesis of dihydroindeno[1,2-b]furans via one-pot three-component reaction in solvent-free conditions

An efficient method was developed for the synthesis of fused dihydroindeno[1,2-b]furans. One-pot three-component reaction of 1,3-indanedione, aromatic aldehyde and pyridinium ylide in the presence of triethylamine under microwave-irradiation in solvent-free conditions afforded dihydroindeno[1,2-b]furans in a diastereoselective manner in excellent yields.     

A stereoselective three-component reaction: The facile synthesis of fluorinated tetrahydropyrimido[1,2-b]benzothiazoles

A one-pot, catalyst- and solvent-free approach has been developed for the stereoselective synthesis of fluorinated tetrahydropyrimido[1,2-b]benzothiazoles. The three-component condensation reaction of an aldehyde and a trifluoromethyl ??-dicarbonyl compound in the presence of 2-aminobenzothizole occurs in high yields at 90 °C.     

Facile one-pot,three-component synthesis of novel bis(heterocycles) incorporating thieno[2,3-b]thiophenes via Michael addition reaction

A synthesis of novel series of bis(2-amino-3-cyano-4H-chromene), bis(2-amino-3-cyanopyrano[3,2-c]chromene), bis(6-amino-5-cyano-1,4-dihydropyrano[2,3-c]pyrazole), and bis(2,7-diamino-3,4,6-tricyanopyrazolo[1,5-a]pyridine) derivatives linked to thieno[2,3-b]thiophene core via ether or ester linkages was reported. The formation of the target compounds presumably proceeds through a three component reaction of the appropriate bis(aldehyde) with 2 M of each of malononitrile and the corresponding active methylene compounds namely; dimedone, 4-hydroxycoumarine, 5-methyl-2,4-dihydro-3H-pyrazol-3-one, or cyanomethylpyrazole in dioxane at reflux in the presence of piperdine as a basic catalyst. The chemical structures of the new compounds were elucidated by several spectral tools.     

Efficient synthesis of chromeno[4,3-b]pyrano[3,4-e]pyridine-6,8-dione derivatives via multicomponent one-pot reaction under mild reaction conditions in water

10-Methyl-7-aryl-7,12-dihydro-6H,8H-chromeno[4,3-b]pyrano[3,4-e]pyridine-6,8-dione derivatives are significant class of compounds and this is critical to develop methods in water using commercially available and non-toxic catalysts. In this paper, an efficient method is introduced for the synthesis of 10-methyl-7-aryl-7,12-dihydro-6H,8H-chromeno[4,3-b]pyrano[3,4-e]pyridine-6,8-dione derivatives. For the synthesis of the desired products, a multicomponent reaction was designed and performed between 4-hydroxycoumarin, an aldehyde, 6-methyl-2H-pyran-2,4(3H)-dione, and ammonium acetate. The products are obtained under green conditions in water in the presence of a catalytic amount of L-proline (10 mol%). The advantage of this method is no need to any toxic solvent, which is critical from the environmental viewpoint. A possible mechanism was suggested, which confirms the role of L-proline in the reaction as the catalyst.

     

Efficient one-pot catalyst-free synthesis of novel coumarin- spiro[indoline-3,4'-pyran] conjugates via three-component domino reaction in aqueous medium

A simple, efficient, eco-friendly and catalyst-free procedure was developed for the construction of novel coumarin-spiro[indoline-3,4'-pyran] conjugates via three-component reactions of various synthetic beta-ketoesters with isatins and malononitrile in aqueous medium. In addition to operational simplicity and absence of tedious separation procedures, being catalyst–free is the prominent advantage of this method.     

Efficient one-pot synthesis of spiro[indoline-3,4′-pyrazolo[3,4-e][1,4]thiazepine]dione via three-component reaction

An efficient one-pot synthesis of spiro[indoline-3,4′-pyrazolo[3,4-e][1,4]thiazepine] dione derivatives via three-component reaction of 5-amino-3-methylpyrazole, isatin, and thioacid is described. This new protocol produces novel heptacyclic spirooxindole derivatives in good yields in comparison to conventional pentacyclic compounds. This method proceeds through a 3-(5-aminopyrazol-3-yl)-3-hydroxy-2-oxindoline intermediate (Baylis-Hillman type adduct), unlike 3-indolylimine (the intermediate like Shiff-Bases) as in conventional methods. The structure of one representative compound has been confirmed by X-ray diffraction analysis.     

Synthesis of benzo[g]indeno[2,1-b]quinoline derivatives via four-component and one-pot synthesis in presence of 3-methyl-1-sulfonic acid imidazolium hydrogen sulfate

A simple and facile synthesis of 12-arylbenzo[g]indeno[2,1-b]quinoline-6,11,13-trione deriv-atives was accomplished by the one-pot condensation of 2-hydroxynaphthalene-1,4-dione, aryl aldehydes, 2H-ind...     

Rapid,clean and efficient one-pot synthesis of thiopyrano[2,3-b]quinolines via domino Michael addition/cyclization reactions

Rapid and efficient one-pot synthesis of thiopyrano[2,3-b]quinolines is described from the reaction of 3-formyl-quinoline-2-thiones with acrylonitrile using economical organic base Et₃N at room temperature. The reaction proceeded smoothly via domino Michael addition/cyclization reactions and did not require dry solvent, inert atmosphere and column chromatography purifications.     

A novel one-pot isocyanide-based four-component reaction: synthesis of highly functionalized 1H-pyrazolo[1,2-b]phthalazine-1,2-dicarboxylates and 1H-pyrazolo[1,2-a]pyridazine-1,2-dicarboxylates

A new protocol has been developed for the efficient synthesis of structurally diverse 1H-pyrazolo[1,2-b]phthalazine-1,2-dicarboxylates and 1H-pyrazolo[1,2-a]pyridazine-1,2-dicarboxylates via a four-component reaction of hydrazine hydrate, dialkyl acetylenedicarboxylates, isocyanides and various cyclic anhydrides such as succinic anhydride, maleic anhydride and phthalic anhydride in ethanol/acetone (1:1) at room temperature in good to moderate yields.