Thermal properties of different transition metal forms of montmorillonite intercalated with mono-, di-, and triethanolammonium compounds

In the present study, different transition metal forms of montmorillonite have been intercalated with mono-, di-, and triethanolammonium cations via d coordination mechanism to investigate their thermal behavior, structural characteristics, surface properties, and elemental composition using TG, XRD, BET, and CHNS techniques. Thermogravimetric analysis showed two thermal transition steps for transition metal-exchanged montmorillonites, which attributed to desorption of the physically adsorbed water and hydrated water, and dehydroxylation of the structural water; whereas for ammonium-montmorillonite complexes, the TG curves showed three thermal transition steps which attributed to desorption of the adsorbed water and dehydration, decomposition of the ammonium cations in the interlayer space of montmorillonite, and the dehydroxylation of the structural water. The thermal analysis of ammonium-montmorillonites affirmed that the molar mass of amine compounds used affects both desorption temperature (position) and the amount of the adsorbed water (intensity). XRD results revealed that the molar mass of amine used has linear relation with the basal spacings of the corresponding ammonium-montmorillonites, indicating structural changes. BET results showed that the molar mass of amines has an inverse effect on the surface area of the studied samples. CHNS analysis for the studied samples quantitatively confirmed the intercalation of ammonium cations into the interlayer space of montmorillonite.     

Thermogravimetric analysis of different molar mass ammonium cations intercalated different cationic forms of montmorillonite

Different cationic forms of montmorillonite, mainly K-, Na-, Ca- and Mg-montmorillonites were intercalated in this study via ion exchange process with mono-, di-, and triethanolammonium cations. The developed samples were characterized by TG, XRD, and CHNS techniques. Thermogravimetric study of ammonium-montmorillonites shows three thermal transition steps, which are attributable to the volatilization of the physically adsorbed water and dehydration, followed by the decomposition of the intercalated ammonium cations and dehydroxylation of the structural water of the modified clay, respectively, while untreated and cationic forms of montmorillonite showed only two decomposition steps. The type of ammonium cation has affected both desorption temperature (Position) and the amount of the adsorbed water (intensity). XRD results show a stepwise change in the crystallographic spacings of montmorillonite with the molar mass of ammonium cation, reflecting a change in the structure of the clay. CHNS data confirm the intercalation of ammonium cations into the interlayer space of montmorillonite and corroborate the effect of the molar mass of ammonium cation on the amount adsorbed by the clay.     

Fluorosulfonyl-containing heterocyclic compounds

Hexafluoroisobutenylidene sulfate is a sulfotrioxidizing agent with respect to various olefins; methylenemethionic acid is formed in the case of ethylene, while the corresponding-sulfones are formed in the case of tetrafluoroethylene and vinylidene fluoride. 2,2-Difluoro-2-hydroxy-ethanesulfonic acid sultone is characterized by a capacity for anionotropic transformations; a number of sulfoacetic acid derivatives were obtained on the basis of this sultone.See [1] for communication III.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 178–182, February, 1973.     

Polynuclear heterocyclic compounds

The cyclization of halogenophenyldiindanedionylmethanes to the corresponding halogenophenyldibenzoylenepyrans and dibenzoylenedihydropyridines is investigated. The latter are readily oxidized to dibenzoylenepyridines.For Part XX see [15].     

Fluorosulfonyl-containing heterocyclic compounds

Salts of hexafluorodimethylmethionic andα-hydrohexafluoro-2-propane-2-sulfonic acids, the amide of the latter, and a number of sulfones containingα-hydrohexafluoroisopropyl, pentafluoroisopropenyl,Β,Β,Β-trifluoroethyl, and methyl groups were obtained by alkaline hydrolysis, alcoholysis, and ammonolysis of hexafluorodimethyl sulfonene trimer.     

Fluorosulfonyl-containing heterocyclic compounds

Depending on the conditions, -hydrohexafluoroisobutyric anhydride, hexafluorodimethylketene, or hexafluoroisobutenylidene sulfate is formed in the sulfotrioxidation of -hydrohexafluoroisobutyric acid. The sulfotrioxidation of -hydrohexafluoroisobutyric anhydride similarly gives hexafluorodimethylketene or hexafluoroisobutenylidene sulfate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 13–15, January, 1973.     

Polyfluorinated heterocyclic compounds

The treatment of 2-phenyl-4-carbomethoxy-6,7,8,9-tetrafluorobenz[f]oxazepin-1,3 (I), 3-benzamido-5,6,7,8-tetrafluorocoumarin (V), and α-benzamido-β-(2-hydroxy-3,4,5,6-tetrafluorophenyl)-acrylic acid (III) with a mixture of glacial acetic acid and a mineral acid gave (IV), the π-complex of 3-hydroxy-5,6,7,8-tetrafluorocoumarin (VII) and benzoic acid. Treatment of (IV) with acetic anhydride gave 3-acetoxy-5,6,7,8-tetrafluorocoumarin (VI) and benzoic acid. Treatment with diazomethane gave 3-methoxy-5,6,7,8-tetrafluorocoumarin (VIII) and methyl benzoate. IV was also obtained from an equimolar mixture of its components. A mechanism for the formation of IV from I is proposed.     

Polyfluorinated heterocyclic compounds

The formylation, aminomethylation, and bromination of 4,5,6,7-tetrafluoroindole were investigated. It is shown that these reactions proceed at the 3 position and that the direction of substitution is in agreement with calculations from the Hiickel molecular orbital method.For Communication V, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1344–1347, October, 1970.     

Polyfluorinated heterocyclic compounds

The treatment of 2-phenyl-4-carbomethoxy-6,7,8,9-tetrafluorobenz[f]oxazepin-1,3 (I), 3-benzamido-5,6,7,8-tetrafluorocoumarin (V), and -benzamido--(2-hydroxy-3,4,5,6-tetrafluorophenyl)-acrylic acid (III) with a mixture of glacial acetic acid and a mineral acid gave (IV), the -complex of 3-hydroxy-5,6,7,8-tetrafluorocoumarin (VII) and benzoic acid. Treatment of (IV) with acetic anhydride gave 3-acetoxy-5,6,7,8-tetrafluorocoumarin (VI) and benzoic acid. Treatment with diazomethane gave 3-methoxy-5,6,7,8-tetrafluorocoumarin (VIII) and methyl benzoate. IV was also obtained from an equimolar mixture of its components. A mechanism for the formation of IV from I is proposed.For part II, see [1].     

Polynuclear heterocyclic compounds

When 2, 3(CO)-benzoylene-4-phenyl-5-keto-7, 7-dimethyl-5, 6, 7, 8-tetrahydroquinoline is catalytically hydrogenated using Adams catalyst, the five-membered ring carbonyl group is reduced to an alcohol group. The acetate, urethane, monoxime, and hydrochloride of the reduction product are prepared. Their IR spectra are measured. When 2, 3 (CO)-benzoylene-4-phenyl-5-keto-7, 7-dimethyl-5, 6, 7, 8-tetrahydroquinoline is reduced by zinc dust and glacial acetic acid, both carbonyl groups are reduced to CH₂, and 2, 3 (CH₂)-benzylene-4-phenyl-5-keto-7, 7-dimethyl-5, 6, 7, 8-tetrahydroquinoline is formed.For Part XIX see [2].     

Polyfluorinated heterocyclic compounds

The synthesis of 4,5,6,7-tetrafluorotryptophan; 4,5,6,7-tetrafluoroheteroauxin; and 4,5,6,7-tetrafluorotryptamine from 4,5,6,7-tetrafluoro-3-(N-piperidinomethyl)indole or its quaternary salt with dimethyl sulfate is described.See [1] for communication VI.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 213–214, February, 1971.     

Reaction of N-tritylamines with nitrogen-containing heterocyclic compounds

Transtritylation occurs during the reaction of N-trityl-N-(β-cyanothethyl)amines with indole, morpholine, and 2- and 4-aminopyridines. The detritylation and transtritylation of the synthesized compounds were studied.     

Amination of heterocyclic compounds with o-benzoylhydroxylamine derivatives

The N-amination of heterocyclic compounds 1a-k with O-benzoylhydroxylamine derivatives 5 was developed and demonstrated to be a superior alternative to existing N-amination methods. A structure-reactivity relationship study was performed on variously substituted O-benzoylhydroxylamine derivatives, leading to the discovery of the novel and more efficient aminating reagents 5h and 5i.     

Fluorosulfonyl-containing heterocyclic compounds

When hexafluoroisobutenylidene sulfate is heated above 80°C, hexafluorodimethylketene is liberated and the inner anhydride of hexafluoro--pyrosulfoisobutyric acid (I) is formed. On storage, anhydride I is spontaneously isomerized to hexafluoroisobutenylidene pyrosulfate, which is converted to the mixed anhydride of pentafluoromethacrylic and fluoropyrosulfonic acids on heating above 130° for many hours. On heating above 160°, I is decarboxylated to give hexafluoropropane-2,2-disulfonic acid anhydride, which is inclined to isomerize to pentafluoropropene-2-pyrosulfonyl fluoride.See [1] for Communication IV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No, 10, pp. 1321–1324, October, 1973.     

Polynuclear heterocyclic compounds

Spectroscopic constants of dibenzoylenepyrans, dibenzoylene-1,4-dihydropyridine, and dibenzoylenepyridines are given. It is shown that the UV spectrum bands of dibenzoylenepyrans are slightly displaced when substituents are changed. Both in character and in band position the absorption curves for dibenzoylene-1,4-dihydropyridines differ from those of the simpler 1,4-dihydropyridines, and the maxima are displaced in a way depending on the substituents. On the other hand, the spectra of anyldibenzoylenepyridines are almost identical, and coincide with the spectrum of dibenzoylenepyridine.For Part XXI see [6].     

Fluorosulfonyl-containing heterocyclic compounds

On the basis of UV and NMR spectroscopy it has been established that with ethers and tertiary amines the cyclic trimer of hexafluorothioacetone dioxide forms donor—acceptor complexes in which there is two-center coordination in the cases of 1,4-dioxane, 1-methylmorpholine, and 1,4-diethylpiperazine, and three-center coordination in the cases of 1,3,5-trioxane and hexamethylenetetramine. The reaction of the trimer with secondary amines has given amides of hexafluoro-2-H-propane-2-sulfonic acid.For Communication VI, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 45–48, January, 1974.     

Polyfluorinated heterocyclic compounds

The condensation of sodium acetoacetate ester with polyfluoroaromatic compounds proceeds according to a type of S-arylation with subsequent ring formation or deacetylation depending on the condition employed.For part III, see [5].     

Stereochemistry of heterocyclic compounds

Summary The stereochemistry of the reaction of 1-alkyl-4-piperidones with phenyllithium depends not only on steric factors, but also on the character of the nitrogen-attached alkyl group. The effect of alkyl groups is associated with fixation of the direction of the dipole of the nitrogen atom, as a result of which the predominant direction of reaction becomes that for which the free electron pair of the nitrogen and the C-O bond of the enolate ion then arising occupy antiparallel directions.