Dimerisation of Knoevenagel Condensation Products obtained from Simple Unconjugated and α,β-Unsaturated Ketones

1999 ◽  
pp. 458-459 ◽  
Author(s):  
Conor N. O'Callaghan ◽  
T. Brian H. McMurry
Keyword(s):  
Knoevenagel Condensation ◽  
Unsaturated Ketones ◽  
Condensation Products

scholarly journals Dimerisation of Knoevenagel Condensation Products obtained from Simple Unconjugated and α,β-Unsaturated Ketones

1999 ◽  
Vol 23 (8) ◽  
pp. 458-459
Author(s):  
Conor N. O'Callaghan ◽  
T. Brian H. McMurry
Keyword(s):  
Knoevenagel Condensation ◽  
Unsaturated Ketones ◽  
Intermediate Products ◽  
Condensation Products ◽  
Dimeric Intermediate

The reaction of 3-acetyl-2 H-1-benzopyran-2-ones with malononitrile affords dicyanomethylene derivatives which dimerise to 1-amino-3,5,5-bis(2-oxo-2 H-1-benzopyran-3-yl)-5-methyl-1,3-cyclohexadiene-2,6,6-tricarbonitrile derivatives and related dimeric intermediate products.

Synthesis, optical, and spectroscopic characterisation of substituted 3-phenyl-2-arylacrylonitriles

2011 ◽  
Vol 65 (1) ◽  
Author(s):  
M. Percino ◽  
Víctor Chapela ◽  
Enrique Pérez-Gutiérrez ◽  
Margarita Cerón ◽  
Guillermo Soriano
Keyword(s):  
Knoevenagel Condensation ◽  
Cyano Group ◽  
Fluorescence Emission ◽  
Emission Spectra ◽  
Fluorescence Emission Spectra ◽  
Condensation Products ◽  
Pyridine Moiety ◽  
Methylene Groups ◽  
Active Methylene ◽  
Spectroscopic Characterisation

AbstractThe Knoevenagel condensation between aldehydes and substrates with active methylene groups was applied to synthesise a series of 3-(4-substituted phenyl)-2-arylacrylonitriles (aryl = phenyl or pyridyl). Chloro-, fluoro-, or dimethylamino-substituted aryls and a cyano group attached to the double bond of acrylonitrile were studied. Previous studies showed that the condensation products were E isomers. The compounds synthesised were: 3-(4-chlorophenyl)-2-phenylacrylonitrile, 3-(4-chlorophenyl)-2-(pyridin-2-yl)acrylonitrile, 3-(4-chlorophenyl)-2-(pyridin-3-yl)acrylonitrile, 3-(4-chlorophenyl)-2-(pyridin-4-yl)acrylonitrile, 3-(4-fluorophenyl)-2-phenylacrylonitrile, 3-(4-fluorophenyl)-2-(pyridin-2-yl)acrylonitrile, 3-(4-fluorophenyl)-2-(pyridin-3-yl)acrylonitrile, 3-(4-fluorophenyl)-2-(pyridin-4-yl)acrylonitrile, 3-(4-dimethylaminophenyl)-2-phenylacrylonitrile, 3-(4-dimethylaminophenyl)-2-(pyridin-2-yl)acrylonitrile, 3-(4-dimethylaminophenyl)-2-(pyridin-3-yl)acrylonitrile, and 3-(4-dimethylaminophenyl)-2-(pyridin-4-yl)acrylonitrile. Structures were confirmed by IR, MS, and NMR spectral data. Molar absorption coefficient, absorbance, and fluorescence emission spectra were compared in order to evaluate the effects of substituents on phenyl and the position of nitrogen in pyridine moiety on the electronic properties of acrylonitrile derivatives prepared.

Reactions of 1-cyano-1-R-2-(5-X-2-furyl)ethylenes with nucleophilic reagents

1984 ◽  
Vol 49 (9) ◽  
pp. 2141-2147 ◽  
Author(s):  
Rudolf Kada ◽  
Viera Knoppová ◽  
Jaroslav Kováč ◽  
Naděžda Mäčková
Keyword(s):  
Knoevenagel Condensation ◽  
Nucleophilic Substitutions ◽  
Condensation Products ◽  
Nucleophilic Reagents

The Knoevenagel condensation of phenylsulphonylacetonitrile and benzoylacetonitrile with 5-X-furane-2-carbaldehydes ( X = Br, NO2, C6H5S, C6H5SO2) has been used for preparation of the respective condensation products 1-cyano-1-fenylsulphonyl-2-(5-X-2-furyl)- and 1-cyano-1-benzoyl-2-(5-X-2-furyl)ethylenes. These condensation products react with nucleophilic reagents which replace the group X at the 5 position of the furane nucleus. These nucleophilic substitutions have been also studied kinetically.

Synthesis and antimicrobial evaluation of some heterocyclic compounds from 3-aryl-1-phenyl-1H-pyrazole-4-carbaldehydes

2018 ◽  
Vol 73 (6) ◽  
pp. 389-397 ◽  
Author(s):  
El Sayed Ramadan ◽  
Essam M. Sharshira ◽  
Ramadan I. El Sokkary ◽  
Noussa Morsy
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Activity ◽  
Heterocyclic Compounds ◽  
Knoevenagel Condensation ◽  
Green Solvent ◽  
Condensation Products ◽  
Diffusion Technique ◽  
Lactam Antibiotic ◽  
Antimicrobial Evaluation

AbstractA new series of chalcones, pyrazolinyl-pyrazoles, pyrazole-4-carbaldehyde oximes, pyrazole-4-carbonitriles, 5-pyrazolyl-1,2,4-triazolidine-3-thiones, and Knoevenagel condensation products was synthesized from 3-aryl-1-phenyl-1H-pyrazole-4-carbaldehydes. Most reactions were carried out either without solvent or in the presence of water as a green solvent. The structure of synthesized compounds was characterized by spectral and elemental analysis. The synthesized compounds were tested in vitro for their antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Candida albicans in comparison with imipenem (intravenous β-lactam antibiotic) and clotrimazole (antifungal medication) as reference drugs by using the agar diffusion technique. 3-Aryl-1-phenyl-1H-pyrazole-4-carbonitriles 8b, 8c, and 8d showed significant antifungal activity against the fungus C. albicans.

Potassium fluoride catalyzed reactions between malononitrile and α, β-unsaturated ketones

1970 ◽  
Vol 48 (19) ◽  
pp. 3064-3075 ◽  
Author(s):  
J. W. ApSimon ◽  
J. W. Hooper ◽  
B. A. Laishes
Keyword(s):  
Carbonyl Group ◽  
Structure Elucidation ◽  
Potassium Fluoride ◽  
Knoevenagel Reaction ◽  
Unsaturated Ketone ◽  
Unusual Structure ◽  
Unsaturated Ketones ◽  
Condensation Products ◽  
Intramolecular Condensation ◽  
Catalyzed Reactions

The preparation and structure elucidation of the condensation products between malononitrile and a variety of α,β-unsaturated ketones using potassium fluoride as catalyst is described. If the carbonyl group of the α,β-unsaturated ketone is hindered, then Michael addition occurs. If, however, the carbonyl group is unencumbered, a Knoevenagel reaction appears to occur first which, in many cases, is then followed by conjugate addition and intramolecular condensation to yield compounds of unusual structure.

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