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1.
Zhenjun Ye 《Tetrahedron letters》2010,51(38):4991-4994
Polyfunctionalized 4H-pyran derivatives bearing fluorochloro pyridyl moiety were readily prepared in high yields via one-pot multicomponent reaction catalyzed by piperidine. This present protocol provides an efficient synthetic route to the target compounds with the characteristics of short reaction time, high yield, and easy separation of the products.  相似文献   

2.
A facile and efficient one-pot three-component synthesis of the spiroacenaphthylene derivatives was achieved, via the reaction of acenaphthequinone, malononitrile/ethylcyanoacetate and various reagents including α-methylencarbonyl compounds/enols.  相似文献   

3.
Some novel functionalized dihydropyrido[2,3-d]pyrimidine derivatives 4 were synthesized using a one-pot three-component reaction of 6-aminouracils 1, aryl aldehydes 2 and 3-cyanoacetyl indole 3 using InCl3 as catalyst.  相似文献   

4.
The one-pot three-component reaction for the synthesis of pyran annulated heterocycles is reported by condensing aromatic aldehydes, ethyl cyanoacetate, or malononitrile and C-H activated acidic compounds in the presence of catalytic amount of 4-(dimethylamino)pyridine (DMAP) in ethanol under reflux conditions. The significant features of the present protocol are simple, environmentally benign, high yields, non-aqueous work-up procedure, no chromatographic separation and recyclability of the catalyst.  相似文献   

5.
A new, simple and efficient synthesis of 4-alkyl-5-methyl-1H-pyrazol-3-ols in water by a two-pot four component reaction of ethyl acetoacetate, hydrazine hydrate, aldehyde and ketone in presence K2CO3 as the catalyst is described. Use of water as the reaction medium, operational simplicity, mild reaction conditions, application of a cost-effective, nontoxic and easily available catalyst with auto-tandem catalysis, wide substrate scope, easy workup and purification process make the protocol highly attractive.  相似文献   

6.
A facile one-step method has been developed for the synthesis of N-protected α-amino aldehyde acetals in moderate to good yields by three-component reaction of fluoroalkanesulfonyl azides, vinyl ethers and alcohol at 0 °C within 10 min. This practical synthetic method provides a convenient and expeditious access to N-per(poly)fluoroalkanesulfonyl α-amino aldehyde acetals.  相似文献   

7.
Abstract

A straightforward and greener PEG-assisted protocol has been disclosed for the cascade synthesis of [1,3]Oxazino quinoline, and chromeno[1,3]oxazin derivatives via three component reaction of multifarious aromatic amines with formaldehyde and 4-hydroxyquinoline-2(1H)-one or 4-methylumbelliferone by using very convenient reaction conditions. This methodology represents a sustainable approach for rapid access to a library of diversity oriented highly pure [1,3]oxazino scaffolds with broad substrate scope.  相似文献   

8.
This work described a one-pot tandem three-component synthesis of 2,4,5-triaryl-2,4-dihydro-3H- 1,2,4-triazol-3-ones using a simple reaction between phenylhydrazines, benzaldehydes and phenyl isocyanates under microwave irradiation and solvent-free conditions in good to excellent yields.  相似文献   

9.
A one-pot, five-component strategy toward the synthesis of new indole substituted pyrrolidine and pyrrolizidine heterocycles through 1,3-dipolar cycloaddition reactions using ninhydrin, 1,2-phenylenediamine, amino acids, 3-cyanoacetyl indoles and aryl aldehydes is described. The features of this procedure were characterized by the mild reaction conditions, high yields, one-pot procedure, and operational simplicity.  相似文献   

10.
Ping He 《Tetrahedron》2005,61(25):6088-6096
Efficient and diastereoselective synthesis of highly substituted fluorinated oxazolidines was achieved via a one-pot three-component reaction of fluoroalkanesulfonyl azides 1, vinyl ether 2 and various aldehydes at 0 °C within 10 min in moderate to good diastereoselectivities (syn/anti). A competing process could be involved in the initial step and an unstable fluorinated aziridine was postulated as the intermediate for these reactions. Additionally, rational transition states were also proposed to elucidate the diastereoselectivities. This synthetic method provides a convenient and expeditious access to N-per(poly)fluoroalkanesulfonyl oxazolidines.  相似文献   

11.
12.
A simple and facile approach to highly functionalized pyrimidone derivatives and indole fused pyrimidones has been developed. The synthesis of substituted pyrimidone derivatives in moderate to good yields involves [4+2] cycloaddition of 1,4-dipoles generated from α,β-unsarurated imines and dimethyl acetylenedicarboxylate (DMAD) with isocyanates as dipolarophiles. Furthermore, the pyrimidones resulted from 2-bromophenyl isocyanate could be transformed into various indole fused pyrimidones via intramolecular palladium-catalyzed Heck reaction under different conditions.  相似文献   

13.
A catalyst-free three-component reaction of indoles, carbonyls, and arenesulfinic acids performed at room temperature provides direct access to biologically important 3-(1-arylsulfonylalkyl)indoles. This process features mild conditions, low cost, broad substrate scope, and high yields, and mechanistically bis(indolyl)methanes were identified as the key intermediates.  相似文献   

14.
A series of new poly-functionalized dihydroquinoline derivatives (26 examples) were synthesized via three-component reactions of aldehydes (1 equiv) and 1-arylethylidenemalononitriles (2 equiv) in ethylene glycol using NaOH as a base promoter under microwave irradiation. During these reaction processes, the domino construction of dihydroquinoline skeleton with concomitant formation of two new cycles was readily achieved in a one-pot operation and in an intermolecular manner.  相似文献   

15.
A series of polysubstituted (3′-indolyl)pyrazolo[3,4-b]pyridine and (3′-indolyl)benzo[h]quinoline derivatives were synthesized via one-pot multicomponent reactions of aldehydes, 3-cyanoacetyl indoles with 5-aminopyrazol or naphthylamine under microwave irradiation. Particularly valuable features of this method include high yields of products, broad substrate scope, short reaction time and straightforward procedure.  相似文献   

16.
The reaction of aldehydes with β-dicarbonyls and electron-rich aromatics was investigated to generate in a multicomponent fashion crossed adducts of biological relevance. 4-Hydroxycoumarin, triacetic acid lactone, indole, and a selection of aliphatic and aromatic aldehydes representative of various electronic and steric conditions were employed. The reaction showed a surprising dependence on the solvent, with 1:1 chloroform–water giving the best yield of heterodimeric adducts. The mechanistic rationale for the formation of hetero- rather than homodimeric adducts is discussed.  相似文献   

17.
《Tetrahedron letters》2014,55(50):6931-6934
This work describes the catalytic ability of Fe3O4@chitosan as an environmentally benign and stable composite nanocatalyst for the synthesis of benzodiazepine derivatives starting from o-phenylenediamine, dimedone, and different aldehydes via a one-pot, three-component reaction at room temperature. High-to-excellent yields, easy work-up, reusability of the nanocatalyst, and non-toxicity are some of the advantages of this protocol.  相似文献   

18.
Reactions of 3-(polyfluoroacyl)chromones with acetoacetamide and ethyl acetoacetate in the presence of ammonium acetate proceed at the C-2 atom of the chromone system with pyrone ring-opening and subsequent cyclization to 5-salicyloyl-2-methyl-6-(trifluoromethyl)nicotinamides, ethyl 5-salicyloyl-2-methyl-6-(trifluoromethyl)nicotinates, and ethyl 5-hydroxy-2-methyl-5-(polyfluoroalkyl)-5H-chromeno[4,3-b]pyridine-3-carboxylates. Similar reaction with β-aminocrotononitrile gave 5-hydroxy-2-methyl-5-(polyfluoroalkyl)-5H-chromeno[4,3-b]pyridine-3-carbonitriles.  相似文献   

19.
Functionalized 3-hydroxymaleic anhydrides were prepared by cyclization of 1,1-bis(trimethylsilyloxy)ketene acetals with oxalyl chloride.  相似文献   

20.
An effective route to functionalized furamide derivatives is described. This involves reaction of N-alkyl-3-oxobutanamides, derived from the addition of amines to the diketene, and dibenzoylacetylene in the presence of triphenylphosphoine. The reactive 1:1 intermediate obtained from the addition of triphenylphosphine to dibenzoylacetylene was trapped by OH-acids such as N-alkyl-3-oxobutanamide to produce functionalized furamide derivatives.  相似文献   

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