Three-component condensation of 2-naphthylamine with aromatic aldehydes and 5-(2-furyl)-1,3-cyclohexanedione

Three-component condensation of 5-(2-furyl)-1,3-cyclohexanedione with 2-naphthylamine and aromatic or heteroaromatic aldehydes afforded 12-aryl(hetaryl)-9-(2-furyl)-7,8,9,10,11,12-hexahydrobenzo[a]-acridin-11-ones possessing two asymmetric carbon atoms (C⁹ and C¹²). The products were found to be formed as mixtures of diastereoisomers.     

New aspects of the aldol condensation of acetylpyridines with aromatic aldehydes

Aldol condensation of acetylpyridines with aromatic aldehydes was studied. A series of new products of cascade reactions were isolated and characterized.     

Three component condensation of 6-quinolylamine with aromatic aldehydes and cyclohexyl 1,3-diketones

A three component condensation of 6-quinolylamine with 4-bromo-or 4-methoxybenzaldehyde, and 1,3-cyclohexanedione or dimedone gave 12-(4-bromophenyl)-and 12-(4-methoxyphenyl)-9,9-dimethyl-8,9,10,12-tetrahydro-7H-benzo[b][4,7]phenanthrolin-11-ones. The reaction intermediates obtained were N-arylmethylene-6-quinolylamines, 2-arylmethylenebis(1,3-cyclohexanediones), 3-(6-quinolylamino)-2-cyclohexenone, and 5,5-dimethyl-3-(6-quinolylamino)-2-cyclohexenone. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No 6, pp. 877–885, June, 2007.     

Condensation of 2-acylcyclohexane-1,3-diones with aromatic aldehydes

Condensation of 2-propanoyl-, 2-butanoyl-, and 2-pentanoylcyclohexane-1,3-diones with aromatic aldehydes in the presence of secondary amines (diethylamine, pyrrolidine, morpholine, piperidine, and hexamethyleneimine) leads to the formation of the corresponding 2-[1-(dialkylamino)-2-alkyl-3-aryl-2-propylidene]cyclohexane-1,3-diones and derivatives of 4H-chromen-4,5(6H)-dione. A primary screening of some of the resulting enamino derivatives for fungicidal activity has been performed.     

Stereoselective aldol condensation of 3,4-dihydro-3-oxo-2H-1,4-benzothiazines: X-ray determination of the aldol stereostructure

3,4-Dihydro-2-methyl-3-oxo-2$\text{H}$-1,4-benzothiazines (1) give erythro-stereoselective aldol condensation. The stereochemistry was determined by single crystal X-ray diffraction. The aldol condensation takes place under kinetic control. The reasons for the observed stereoselectivity are discussed.     

Structure and reactivity of the condensation products of aromatic amines with aliphatic aldehydes

A number of previously undescribed propylidenearylamine dimers have been synthesized by the interaction of propionaldehyde with a series of para-substituted anilines(R=H, CH₃, OCH₃, F, Cl, Br, I) and with-naphthylamine. The structure of the bis-propylidenearylamines has been established by a study of their IR and UV spectra. It has been shown that all the bis-propylidenearylamines, except for bis(propylidene-p-fluoroaniline), have the structure of 2-ethyl-3-methyl-4-arylamino-1, 2, 3, 4-tetrahydroquinolines. The dipole moments of the bis(propylidene-p-R-anilines) have been determined. Comparison of the values obtained with the calculated values indicates that the most favorable molecular conformation of the bispropylidenearylamines is a tetrahydroquinoline half-chain with quasi-equatorial positions for the 4-NHAr and NH groups and an equatorial 3-CH₃ group. In contrast to the bis-ethylideneanilines, we did not succeed in finding other stable conformers for the bis-propylidene derivatives. It has been established that bis (propylidene-p-fluoroaniline) has the 1, 3-bis (p-fluorophenylamino)-2-ethyl-1-hexene structure.For communication VI, see [1].     

Spectrophotometric determination and kinetic studies of condensation of aromatic aldehydes with 1,3-dimethylbarbituric acid

The condensation reaction of 1,3-dimethylbarbituric acid with aromatic aldehydes in ethanol has been investigated spectrophotometrically at 25–35°C. The reaction follows overall second-order kinetics, first-order each in reactant. From the dependence of the rate constants on temperature, activation parameters have been calculated. The rate of condensation increases with the presence of electron donating groups on the aromatic ring of the aldehyde. The rate-determining step involves dehydration of the aldol intermediate. The reaction was found to be catalyzed by HCl solutions. Based on this reaction, determination of 10 aromatic aldehydes in a concentration range of 0.13–70.25 μg/ml is proposed. The method was applied for determination of barbituric and 1,3-dimethylbarbituric acids also.     

4-(5-Methoxy-2-oxazolyl)naphthalic anhydride and products of its condensation with aromatic amines

4-(5-Methyl-2-oxoazolyl)naphthalic anhydride was synthesized by condensation of 4-chloroformylnaphthalic anhydride with aminoacetone and subsequent cyclization of the resulting amide. Luminescing methyl-substituted N-phenylnaphthalimide and 1,8-naphthoylene-1,2-benzimidazple were obtained by condensation of this product with aniline and o-phenylenediamine, respectively. The relationship between the structures of the products and their electronic absorption and luminescence spectra was investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 883–885, July, 1976.     

Reaction of 2-(2-oxo-2-arylethylidene)-2,3-dihydropyrimidine-4(1H)-ones with aldehydes

2-(2-Oxo-2-arylethylidene)-2,3-dihydropyrimidine-4(1H)-ones react with aromatic and heteroaromatic aldehydes to form the unsaturated ketones, whereas in the case of 3- and 4-benzaldehydes the corresponding trans-2-styrylpyrimidine-4(3H)-ones were obtained. A possible mechanism of hydrolytic cleavage of the product of condensation of 2-(2-oxo-2-phenylethylidene)-2,3-dihydropyrimidine-4(1H)-one with paraformaldehyde under acid catalysis and mechanochemical activation has been discussed.     

Interaction of 2-(2-azahetaryl)-3-oxo-4-chlorobutane nitriles with esters of aromatic amino acids

The reaction of 2-(2-azahetaryl)-3-oxo-4-chlorobutane nitriles with esters of aromatic acids was studied. A series of 1H,4H-3-(2-azahetaryl)pyrrolo[1,2-a] quinazoline-2,5-diones and 1-aryl-2-amino-3-(2-azahetaryl)-4-(5H)-oxopyrroles was obtained. The reaction of the latter with hydrazine and acetic anhydride was investigated. Taras Shevchenko Kiev University, Kiev 252033, Ukraine. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1412–1418, October, 1999.     

Linear condensation polymers of aromatic 1,3-diamines with 3-pyridinealdehyde

In the presence of one equivalent of acid, m-phenylenediamine and 2-methyl m-phenylenediamine react with pyridine-3 aldehyde with C alkylation to produce linear polymers, poly(4,6-R-methylene m-phenylenediamine) and poly(4,6-R-methylene 2-methyl m-phenylenediamine). These were characterized by UV, IR, and NMR spectroscopy. Comparison with model compounds confirmed the above structures. A secondary reaction noted at 25°C and higher for the polymer was the oxidative coupling of two neighboring aromatic diamines to produce substituted 2,7-diamino acridine groups along the chain.     

Ketene bis(trimethylsilyl) acetals. Cross-aldol condensation with aldehydes. Stereochemistry of the reaction

The titanium tetrachloride catalyzed condensation of the title acetals with aldehydes, leads to threo or erythro β-hydroxyacids with good stereoselectivity which depends mainly on the nature of the acetal counterion.     

Cu(II)-catalyzed enantioselective aldol condensation between malonic acid hemithioesters and aldehydes

A mild, decarboxylative, aldol-type addition of malonic acid hemithioesters to aldehydes has been shown to occur with up to 39% enantioselectivity when the reaction was carried out in the presence of catalytic amounts of a Cu(II) salt, an enantiopure, tartaric acid-derived bis-benzimidazole and an achiral base.     

Condensation of 2-(3,4-methylenedioxyphenyl)-5,6-benzolepidine methiodide with aromatic aldehydes

2-(3,4-Methylenedioxyphenyl)-5,6-benzolepidine methiodide enters into condensation with aromatic aldehydes in absolute alcohol in the presence of piperidine to give styryl dyes. The effect of various substituents in the styryl residue on the position of the absorption maxima of the dyes was studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 689–690, May, 1973.     

Synthesis of 3-[5-anilino-(2,3-d)-dioxole-1,3]-1-oxo-1,3-dihydro-2-benzofurane

A microscale synthesis (500 mg) of the product 3-[5-anilino-(2,3-d)-dioxole-1,3]-1-oxo-1, 3-dihydro-2-benzofurane (COR.01.126) is described. This method, which requires only four steps, is principally available for the ¹⁴C-labeled synthesis with labeled phthalic anhydride as starting material.