Polyfuryl(aryl)alkanes and their derivatives 16. Convenient path to benzofuran ketones

2-(3-Oxobutyl)-3-(5-methyl-2-furyl)benzofurans were synthesized by the recyclization of 2-hydroxyarylbis(5-methyl-2-furyl)methanes in methanol saturated with hydrogen chloride. They can also be obtained by the reaction of salicylaldehydes and sylvane in an ethanol solution of hydrogen chloride.For Communication 15, see [1].Severo-Osetinsk State University, Vladikavkaz, Russia. Kubansk State Technological University, Krasnodar 362040, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 603–607, May, 1998.     

Synthesis of crown-containing 2-styrylbenzothiazoles. Effect of alkali metal cations on the condensation of crown-ether benzaldehydes with 2-methylbenzothiazole

Methods for the synthesis of unknown 2-styrylbenzothiazoles containing crown ether moieties with different combinations of O, S, and N-heteroatoms based on the Wittig reaction or condensation of 2-methylbenzothiazole with crown-ether benzaldehydes in the presence of strong bases or acids are proposed. The condensation in the presence of bases is accompanied by complex formation with participation of the crown ether moiety of the benzaldehyde. The complex formation has a pronounced influence on the yield of the target product and the pattern of condensation of 2-methylbenzothiazole with crown-ether benzaldehydes.     

Hydrolysis and polycondensation of ethyl silicates. 3. Hydrolysis and polycondensation of ETS40 (ethyl silicate 40) in the presence of water colloidal silica sols

The hydrolysis and condensation of ETS40 (ethyl silicate 40) in the presence of water colloidal silica sols were studied with the aid of gas chromatography, potentiometry and gelation tests. The acids HCl, H₂SO₄, HNO₃, HCOOH, (COOH)₂ and p-toluenesulfonic acid were used as catalysts.

Water—ethanol solutions of the reaction products of the hydrolysis and condensation of ETS40 in the presence of water colloidal silica sols were stable for more than 2 years.

This stability was caused by a low water content in the water—ethanol solutions of the reaction products, a stable pH of about 2.0 and by bonded or non-bonded interactions between ETS40 hydrolysates (ethoxyhydroxysiloxanes) and large particles of water colloidal silica sols.     

Fused s-triazino heterocycles. VIII. 1,3,4,6,9b-pentaazaphenalenes. Reactions of a methyl and bromomethyl side chain

Enhanced reactivity of the methyl group of 2-t-butyl-5-methyl-1,3,4,6,9b-pentaazaphenalene allowed acetic anhydride-catalyzed condensation reactions with several aromatic aldehydes, and base-catalyzed alkylation reactions with several alkyl halides to take place, albeit in low yields. Of the many nucleophiles tried, only salts of carboxylic acids, in the presence of 18-crown-6, were able to displace bromine from 2-(bromomethyl)-5-methyl-1,3,4,6,9b-pentaazaphenalene.     

Zwitterion radicals and anion radicals from electron transfer and solvent condensation with the fingerprint developing agent ninhydrin.

Ninhydrin (the fingerprint developing agent) spontaneously dehydrates in liquid ammonia and in hexamethylphosphoramide (HMPA) to form indantrione, which has a sufficiently large solution electron affinity to extract an electron from the solvent (HMPA) to produce the indantrione anion radical. In liquid NH(3), the presence of trace amounts of amide ion causes the spontaneous formation of an anion radical condensation product, wherein the no. 2 carbon (originally a carbonyl carbon) becomes substituted with -NH(2) and -OH groups. In HMPA, the indantrione anion radical spontaneously forms condensation products with the HMPA to produce a variety of zwitterionic radicals, wherein the no. 2 carbon becomes directly attached to a nitrogen of the HMPA. The mechanisms for the formation of the zwitterionic paramagnetic condensation products are analogous to that observed in the reaction of ninhydrin with amino acids to yield Ruhemann's Purple, the contrast product in fingerprint development. The formation of anion and zwitterionic radical condensation products from ninhydrin and nitrogen-containing solvents may represent an example of a host of analogous polyketone-solvent reactions.     

Oxidative Reactions of Azines. 11. The Influence of Manganese Dioxide on the Reaction of Tetrahydropyridines with Formaldehyde: Synthesis and Molecular Structures of 3-Oxa-7-azabicyclo[3.3.1]- and 6-Oxa-2-azabicyclo[3.2.1]octanes

New derivatives of piperidino[4,5-d]dioxane and 3-oxa-7-bicyclo[3.3.1]nonane were obtained by the oxidatively catalysed condensation of 4-aryl-1,2,3,6-tetrahydropyridines with formaldehyde. The direction of this reaction is sharply altered in the presence of manganese dioxide to give 6-oxa-2-azabicylo[3.2.1]octan-4-one — the product of the oxidative condensation of a new type.     

Synthesis of heterocyclic compounds. II. A simple one-step synthesis of pyridines from aldehydes and malononitrile

The condensation of several aldehydes with malononitrile in the presence of a alcohol-alkoxide system provides a new simple, one-step route to 4-substituted 2-amino-3,5-dieyano-6-alkoxy-pyridines. The best results are obtained with the aromatic aldehydes. The structure of these compounds was established from a study of their infrared, ultraviolet and nuclear magnetic resonance spectra.     

Phenolic derivatives of 2-pyrone. I.

The condensation of hydroxy- and methoxyacetophenones with 1,1,1,3-tetrachloro-3-ethoxypropane or β, β-dichloroacrolein in an acid medium has yielded a number of dichlorodienyl hydroxyphenyl ketones which are converted into the corresponding 2-pyrones in acetic or propionic acids in the presence of phosphoric acid.     

Acetylene derivatives. Communication 177. Condensation of aromatic and aliphatic-aromatic ketones with acetylene under pressure. Part III.

Summary In presence of potassium hydroxide powder, aliphatic-aromatic and aromatic ketones of the aceto- and benzo-phenone types condense smoothly with acetylene at a pressure of 5–10 atm with formation of the corresponding tertiary acetylenic alcohols in yields of more than 90%. When the 2-aryl-3-butyn-2-ols so obtained are selectively hydrogenated over a palladium catalyst, 2-aryl-3-buten-2-ols are obtained in almost quantitative yield, and dehydration of these gives 2-aryl-1,3-butadienes, which are extremely reactive in polymerization (dimerization) reactions and in the diene condensation.     

Synthesis and properties of furan derivatives. 5. Synthesis of 2-substituted benzoxazoles containing furan fragments

The condensation of imidates and imidate hydrochlorides of furan acids with o-aminophenols gives furyl derivatives of 2-substituted benzoxazoles. Such compounds are also formed in the reaction of furan acids with o-aminophenol in the presence of boric acid.Communication 4, see [1].I. M. Gubkin State Petroleum and Gas Academy, 117917 Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 896–901, July, 1996. Original article submitted April 16, 1996.     

Synthesis and some transformations of sulfides of the thiophene series

Some 2-substituted 4-keto-2,3-dihydrothieno[3,2-e]-1,3-thiazines were obtained by condensation of 2-mercapto-5-ethylthiophene-3-carboxamide with aldehydes and ketones in the presence of gaseous HCl.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 909–910, July, 1972.     

Diazocarbonyl derivatives of heterocycles. 6. Intramolecular reactions of 2-carbomethoxy-3-diazoacetylquinoline

Treatment of 2-carbomethoxy-3-diazoacetylquinoline with mineral acids results in an intramolecular reaction leading to the formation of 6H-2,5-dioxopyrano-[3,4-b]quinoline; in the presence of bases the intramolecular condensation product is 2-diazo-1,3-dioxocyclopenteno[4,5-b]-quinoline. Treatment of 2-carbomethoxy-3-diazoacetylquinoline with sodium methoxide results in a reversible intramolecular rearrangement via migration of the diazomethine fragment and formation of the isomeric 3-carbomethoxy-2-diazoacetylquinoline.For communication No. 5 see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 959–962, July, 1987.     

Phthalocyanines and related compounds: XLII. Synthesis of phenyl-substituted tetraazachlorins and tetraazabacteriochlorins

New oxidation-resistant hexaphenyl-substituted tetramethyltetraazachlorin, its nickel complex, and tetraphenyl-substituted octamethyltetraazabacteriochlorin and octamethyltetraazaisobacteriochlorin nickel complexes were synthesized for the first time by mixed condensation of diphenylm aleonitrile with tetramethylsuccinonitrile in the presence of lithium dimethylaminoethoxide or nickel chloride. The products were characterized by electronic absorption, ¹H NMR, and mass spectra. Mixed condensation of diphenylsuccinonitrile with phthalonitrile in the presence of nickel chloride was found to give nickel complexes of phenylsubstituted benzo-fused tetraazaporphyrins rather than their hydrogenated derivatives.     

Syntheses based on furancarboxylic acid amides. 1. Synthesis and structure of 2-(5-R-2-furyl)-4-oxoquinazolines

2-(5-R-2-Furyl)-4-oxoquinazolines are formed in the condensation of furancarboxylic acid primary amides with anthranilic acid in the presence of phosphorus oxychloride. It was determined by x-ray diffraction analysis, IR and PMR spectroscopy, and mass spectrometry that a labile hydrogen atom is bonded to the nitrogen atom in the 3-position and that the molecule has an s-NH,0-trans conformation.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1463–1466, November, 1989.     

Synthesis and some transformations of thioesters of thienylacrylic acid

A number of thioesters of thienylacrylic acid were obtained by the condensation of 2-formylthiophene and 5-bromo-2-formylthiophene with acetylenic thioethers in the presence of boron trifluoride etherate. The reaction of the condensation products with hydrazine hydrate is accompanied by intramolecular cyclization to form the corresponding pyrazolines. The IR spectra of the synthesized compounds are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1348–1349, October, 1971.     

Pyridinethiones. VIII. The aldol and wittig condensations of 3-formyl-2(1H)-pyridones, -thiones and -selones. Preparation of new cyanopyridones

Condensations of 1-substituted-3-formyl-2(1H)-pyridones, -thiones and -selones with methyl ketones such as acetophenone give the corresponding chalcones in high yields. Geometry at the vinyl hydrogens is E. These chalcones can be cyclized with ethyl cyanoacetate in the presence of ammonium acetate to form new 3-cyano-2(1H)-pyridones. An effective “one-pot” preparation is worked out and an intermediate from the cyclization reaction is isolated. Via the Wittig reaction it is possible to prepare condensation products from 1-substituted-3-formyl-2(1H)-pyridinethiones and -selones with mainly Z geometry at the vinyl hydrogens.     

Studies on phenothiazines. Part 7. Synthesis of 3-substituted 2-aminobenzenethiols and their conversion into phenothiazines

Synthesis of substituted 1-nitrophenothiazines is reported by the Smiles rearrangement in situ, which involves condensation of 3-chloro or methyl-2-aminobenzenethiol with o-halonitrobenzenes (2,4,6-trinitochloro-benzene, 1,4-dichloro-2,6-dinitrobenzene, 2,4,6-tribromo-1,3-dinitrobenzene) in the presence of ethanolic sodium hydroxide. Ir and mass spectral studies are included.     

Catalytic and Physicochemical Properties of Oxidative Condensation Products in the Oxidative Dehydrogenation of Propane by Sulfur Dioxide on SiO2

The effect of the deposition of oxidative condensation products in the reaction of oxidative propane dehydrogenation in the presence of SO₂ on the catalytic, acid–base, and texture characteristics of silica was studied. It was found that the oxidative condensation products exhibited high catalytic activity in this reaction. The carbonization of silica from 0 to 40 wt % was accompanied by an increase in the yield of propylene from 3.4 to 46 mol % (640°C; a C₃H₈/SO₂/He + N₂ mixture, 10 : 10 : 80 vol %). Further accumulation of condensation products resulted in a considerable decrease in the pore volume and radius; this imposed diffusion limitations on both propane conversion and selectivity to propane conversion products. The nature of active and deactivated condensation products was studied by DRIFT spectroscopy, diffuse-reflectance UV–VIS spectroscopy, EPR spectroscopy, XPS, thermal analysis, and electron microscopy.     

1,2,3-benzotriazines. I. The synthesis of some benzimidazo [1,2-c][1,2,3]-benzotriazines and naphth[1′,2,(2′,1′):4,5]imidazo[1,2-c][1,2,3]benzotriazine

A number of substituted benzimidazo[1, 2-c][1,2,3]benzotriazines were prepared by the diazotization of the appropriate 2-(o-aminophenyl)benzimidazoles. Diazotization of 2-(o-aminophenyl)naphth[1,2-d]imidazole yielded a new heterocyclic ring system. Various methods of preparation of 2 - (o-aminophenyl)benzimidazoles were investigated. The condensation of o-phenylenediamines with anthranilic acids, in the presence of polyphosphoric acid, provided a convenient route to 2-(o-aminophenyl)benzimidazoles but in several cases the products were contaminated with considerable amounts of 6-(o-aminophenyl)benzimidazo[1,2 -c]quinazolines. 2 - (o-Aminophenyl)benzimidazoles were also obtained by the catalytic hydrogenation of 2-(o-nitrophenyl)benzimidazoles which resulted from the condensation of an o-phenylenediamine with an o-nitrobenzaldehyde in ethanol, nitrobenzene or acetic acid. When the condensation was carried out in nitrobenzene, small amounts of 2-(o-aminophenyl)benzimidazoles were also formed. The Weidenhagen synthesis, which involves the reaction of an aromatic diamine with an aldehyde in the presence of copper acetate and subsequent decomposition of the cuprous salt of the benzimidazole, yielded 2-(o-aminophenyl)benzimidazoles instead of the expected 2-(o-nitrophenyl)benzimidazoles when the decomposition was carried out in ethanol. When the cuprous salt was treated with hydrogen sulfide in dilute hydrochloric acid, a mixture of amino- and nitrobenzimidazoles resulted. The ultraviolet and infrared spectra of all the compounds prepared were examined.     

A concise synthesis of 2-benzoyl-1-indanones and 1-indanones from 2-aryl-1-tetralones

Abstract

Methyl-2-(3-oxo-3-aryl) benzoates derived from acid catalyzed air oxidative fragmentation of 2-aryl-1-tetralones were efficiently undergone intramolecular-Claisen condensation in the presence of potassium tertiary butoxide. The resulting 2-benzoyl-1-indanones formed in two-step ring contractions were further subjected to indium triflate mediated retro-Claisen condensation to get 1-indanones.