Polyfuryl(aryl)alkanes and their derivatives 9. Polyfuryl(aryl)methanes in the diels-alder reaction

The reaction of polyfuryl(aryl)methanes with N-(3,5-dichlorophenyl)maleimide has been studied. It was found that tetrasubstituted methanes do not react. Difurylmethane, gem-difurylethane, gem-difurylethane, and trifurylmethane form mono- and diadducts, and difurylarylmethanes form only monoadducts. The molecular and crystal structure of the diadduct of gem-difurylethane- gem-bis {4-aza-7-methyl-10-oxa-4-(3,5-dichlorophenyl)tricyclo-[5,2,1,0 _2,6]deca-8-en-3,5-dion-1-yl}ethane has been studied.For Communication 8, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 751–758, June, 1993.     

Furyl(aryl)methanes and Their Derivatives. 23. Simple Synthesis of Benzo[b]furan Derivatives from 2-Alkylfurans

New derivatives of benzo[b]furan were obtained during successive bromination and dehydrobromination of alkanones containing a gem-difurylmethyl fragment. A mechanism is proposed for the transformations that occur.     

Palladium-catalyzed direct arylation of aryl(azaaryl)methanes with aryl halides providing triarylmethanes

Direct arylation of aryl(azaaryl)methanes with aryl halides takes place at the benzylic position in the presence of a hydroxide base under palladium catalysis to yield triarylmethanes.     

Synthesis of aryl(γ-pyridyl)methanes and their conversion to substituted benzo[g]isoquinolines

New substituted pyridine bases of the aryl(-pyridyl)methane type were obtained from 1,2,5-trimethyl-4-piperidone by successive transformations. The new substituted pyridine bases were catalytically dehydrocyclized to di(tri)methylbenzo[g]isoquinolines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1077–1084, August, 1976.     

First Synthesis of Bis(di(indolyl)aryl)methanes From Bis(salicylaldehydes)

In this article, a simple method for the synthesis of bis(di(indolyl)aryl)methanes is described. The iodine‐catalyzed (5 mol %) reaction of indoles with various bis(salicylaldehyde) derivatives affords the bis(di(indolyl)aryl)methanes in excellent yields. The reaction works well under mild reaction condition with shorter reaction time.     

Polyfuryl(aryl)alkanes and their derivatives. 14. Halochromism of polyfuryl(aryl)alkanes

It was concluded on the basis of the similarity between the electronic spectra of difurylarylmethanes and trifurylalkanes and the spectra of the corresponding arylfurylcarbinols and difurylcarbenium perchlorates in concentrated sulfuric acid that the appearance of color in the solutions of polyfuryl(aryl)alkanes in concentrated sulfuric acid results from their disproportionation at the carbon-carbon bond with the elimination of the furan ring. The disproportionation of difurylalkanes, containing a methine hydrogen atom at the central carbon atom, under these conditions is accompanied by hydride transfer.For Communication 13, see [1].Kubansk State Technological University, Krasnodar. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 738–741, June, 1996. Original article submitted February 21, 1996.     

Synthesis of aryl/alkyl(2,2′-bis-3-methylindolyl)methanes and aryl(3,3′-bis indolyl)methanes promoted by secondary amine based ionic liquids and microwave irradiation

Aryl/alkyl(2,2′-bis-3-methylindolyl)methanes and aryl(bis-3,3′-indolyl)methanes are synthesized in high yield using ionic liquids mediated by microwave. Reaction conditions and product recovery are simple and ionic liquids could be recycled.     

Polyfuryl(aryl)alkanes and their derivatives. 5. Cations and radicals in the polyfuryl(aryl)methane series

The perchlorates of trifuryl- and difuryl(aryl)carbene have been prepared by the oxidation of polyfuryl(aryl)-methanes with trityl perchlorate and have been characterized. The temperature dependence of the PMR and ¹³C NMR spectra of the cations suggests that they exist in solution in the form of various rotamers. X-ray diffraction has been used to establish that the tris(5-methyl-2-furyl)carbene perchlorate molecule is a symmetrical propeller in which each furan ring is twisted from the plane by 10.4°. Reduction of the corresponding perchlorates on a zinc mirror in tetrahydrofuran gives stable polyfuryl(aryl)-methane radicals which were recorded by ESR spectroscopy.For Communication 4, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 329–337, March, 1993.     

Polyfuryl(aryl)alkanes and their derivatives

The reduction of 2-nitrophenyldifurylmethane with SnCl₂ leads to an indolenyl ketone as a result of intramolecular heterocycloaddition of the intermediately formed nitroso derivative. During the reduction of 2-nitroaryldifurylmethanes in the Zn+HCl or NH₂NH₂·H₂O+Pd/C systems, 2-aminoaryldifurylmethanes are formed; when treated with trityl perchlorate, their acetyl derivatives are converted into indolo[2,3-h]-1-oxazulenium perchlorates.For Communication 14, see [1].Kubansk State Technological University, Krasnodar. Severo-Osetinsk State University, Vladikavkaz. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1614–1621, December,1997.     

Phthalones and their structural analogs (review)

This review is devoted to research on the synthesis, reactivities, practical application, and structural problems of compounds of the phthalone series, primarily pyrophthalones and quinophthalones. The properties and peculiarities of the structures of the indicated compounds are compared with structural analogs that contain other heterocyclic substituents and other β-dicarbonyl systems and also with other betainelike derivatives of β-dicarbonyl compounds. Problems in the development of the chemistry of phthalones are discussed.     

Polyfuryl(aryl)alkanes and their derivatives. 12. C-fur bond cleavage in the series of polyfuryl(aryl)alkanes

Reactions taking place with cleavage of the C-Fur bond are examined. It was established that disproportionation in two directions, leading to the formation of tris(5-methyl-2 furyl)methane, takes place when 3, 4dimethoxyphenylbis(5-methyl-2 furyl)methane is boiled in an acidic medium. The acid-catalyzed reaction of 5-methylfurfural with ethylene glycol leads to the formation of either 2-(S-methyl-2 fury!)-1,3-dioxolane or tris(S-methyl-2 furyl)methane, depending on the catalyst. The treatment of 2-(S-methyl-2 fury!)-1,3-dioxolane or gem-tris(5. methyl-2 furyl)ethane with triryl perchlorate leads to tris(5-methyl-2 furyl)carbenium or bis(5-methyl-2-furyl)methylcarbenium perchlorates respectively.For Comminication 11, see [1]Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 175–179, February, 1996.     

Polyfuryl(aryl)alkanes and their derivatives. 2. Trifurylalkanes and mechanism of their formation

Alkylfurans react with carboxylic acid anhydrides and chlorides in benzene in the presence of catalytic amounts of perchloric acid to give trifurylalkanes. The mechanism of the reaction, which is a consecutive process with the successive formation of an acylfuran, an alkyldifurylcarbinol, and a trifurylalkane, is examined. Intermediates, including an alkyldifurylcarbonium perchlorate, were isolated and characterized.See [1] for Communication 1.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 592–596, May, 1983.     

Trialkylsilylmethyltris(hydroxymethyl)methanes

Trialkylsilylmethyltris (hydroxymethyl) methanes were synthesized by the reaction of -trialkylsilylpropanals with formaldehyde.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2860–2861, December, 1989.     

Aryl(7-indolizinyl)methanes

Aryl(6-methyl-2-phenyl-7-indolizinyl)methanes were obtained by quaternization of aryl(-pyridyl)methanes with bromoacetophenone and subsequent cyclization of the quaternary salts with 40% potassium carbonate solution (the Chichibabin method). The stable 2, 5-dimethyl-4-(2,4-dimethylbenzyl)pyridinium benzoylmethylid, which was converted to an indolizine by the action of Al₂O₃, was isolated by the action of a 10% potassium carbonate solution on the corresponding quaternary salt. The ability of 3-unsubstituted indolizines to undergo protonation in both the 3 and 1 position was shown on the basis of the PMR spectra. The aryl(7-indolizinyl)methanes are selectively hydrogenated thoroughly over rhenium heptasulfide in the indolizine ring to give tetra or octahydro derivatives without involvement of the aryl groups. Data from the IR, PMR, and mass spectra are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 646–649, May, 1977.     

Polyfuryl(aryl)alkanes and their derivatives. 4. Synthesis of furyldiarylmethane derivatives

A number of substituted furyldiarylmethanes were obtained by the reaction of furan derivatives with secondary aromatic alcohols.See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 307–308, March, 1984.     

A simple synthesis of di(uracilyl)aryl methanes and 1,ω-bis[di(uracilyl)methyl]benzenes

Di(uracilyl)aryl methanes and their homologues, 1,ω-bis[di(uracilyl)methyl]benzenes, have been synthesized in good yields through the HBr-acetic acid catalyzed condensation of 1-alkyl-/1,3-dialkyluracil derivatives with readily available aryl aldehydes and dialdehydes.     

A novel substrate controlled chemoselective synthesis of aryl bis(thiazole-2-imine)methanes from 2-aminothiazoles and aldehydes

Aryl bis(thiazole-2-imine)methanes have been synthesized chemoselectively for the first time by an unusual reaction between 5-aryl substituted 2-aminothiazoles and aromatic aldehydes with excellent yield using inexpensive and easy available acetic acid as a catalyst under mild conditions. The present protocol was constructed through N-C bond formation by the condensation and nucleophilic addition reactions.     

Cyclic azomethines and their hydrogenated derivatives. (Review)

The literature data on the methods of synthesis and chemical properties of cyclic azomethines, mainly isoquinoline derivatives, have been correlated. Examples of biologically active compounds of the 3,4-dihydro- and 1,2,3,4-tetrahydroisoquinoline are given.Institute of Technical Chemistry, Russian Academy of Sciences, Ural Branch, Perm 614600, Russia; Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 579–604, May, 2000.