Synthesis of heterocyclic compounds from 2-phenyl-1,2,3-triazole-4-formylhydrazine

2-Phenyl-1, 2, 3-triazole-4-formylhydrazine (2) was prepared by hydrazinolysis of the corresponding ester 1. Reaction of 2 with CS₂/KOH gave the oxadiazole derivatives (3) which via Mannich reaction with different dialkyl amines furnished 3-N, N-dialkyl derivatives (4a–c). Also, condensation of 2 with appropriate aromatic acid in POCI₃ yielded oxadiazole derivatives (5a–c), or with aldehydes and ketones afforded hydrazones (6a–c). Cyclization of (6a–c) with acetic anhydride gave the desired dihydroxadiazole derivatives (7a–c). On the other hand, reaction of dithiocarbazate (8) with hydrazine hydrate gave the corresponding triazole derivative (9) which on treatment with carboxylic acids in refluxing POCI₃ yielded s-triazole [3, 4–b]-1, 3, 4-thiadiazole derivatives (10a–b). The structures of all the above compounds were confirmed by means of IR, ¹H NMR, MS and elemental analysis.     

Synthesis of thiocarbonyl and heterocyclic compounds from 2-methylene-1,3-dithietanes

2-Methyl-1,3-dithietanes bearing electron withdrawing groups on the methylene carbon atom were synthesized and their reactivities were studied. These compounds readily underwent a ring-opening reaction with a variety of nucleophic reagents such as amines, alcoholate and thiolate anions to yield thioamides, thionoesters and dithioesters, respectively. The products were applied for synthesis of heterocycles such as thiadiazoles, isothiazolones and pyrazoles.     

Novel metallomesogens derived from heterocyclic benzoxazoles

The synthesis, mesomorphic behavior, and optical properties of a new series of transition metal complexes 1a and 1b derived from benzoxazoles 2 are reported. The crystal and molecular structure of copper complex of 6-dodecyloxynaphthalene-2-carboxylic acid 4-(6-hexyloxybenzooxazol-2-yl)-3-hydroxyphenyl ester 1a (n=6; m=12) was determined by means of X-ray structural analysis, and it crystallizes in the triclinic space group P-1. The geometry at copper center is perfectly square-planar, and the overall molecular shape is considered as rod-shape. All precursors 2 with shorter chains (n=0, 1, 4) exhibited nematic, and all others with longer chains (n=6, 7, 8, 10, 12) formed N/SmC phases. In contrast, all copper(II) complexes 1a and palladium complexes 1b formed N phase. On the other hand, the temperature range of mesophase in compound 1a was wider than those in compound 1b. The difference of the mesomorphic properties in compounds 1a and 1b was attributed to the geometry or/and the size of the metal center. The fluorescent properties of these compounds were also examined.     

Synthesis of heterocyclic compounds from 4-formylpyrazoles

Formylation of pyrazole and 2,5-dimethylpyrazole gave a number of pyrazole-containing aldehydes, which can be used to obtain chromenes, tetrahydrochromenes, 1,4-dihydropyrano[2,3-c]pyrazoles, pyrano[3,2-c]chromenes, thiochromeno[4,3-b]pyrans, pyrano[3,2-c]-quinolines, and thiazolo[3,2-a]pyridines.     

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.     

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].     

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].     

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.     

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].     

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].