3-Oxy-5-phenyl-1<Emphasis Type="Italic">H</Emphasis>-1,2,3-triazole-4-carboxylic Acid. Synthesis,Structure, and Properties

The structure of 3-oxy-5-phenyl-1H-1,2,3-triazole-4-carboxylic acid was determined both experimentally (by the X-ray diffraction method) and by quantum-chemical calculations. Alkylation of 3-oxy-5-phenyl-1H-1,2,3-triazole-4-carboxylic acid (as crystal hydrate) with methyl iodide, depending on the reactant ratio, gives 1-methoxy-4-phenyl-1H-1,2,3-triazole-5-carboxylic acid and methyl 1-methoxy-4-phenyl-1H-1,2,3-triazole-5-carboxylate. Nitration of the title compound under mild conditions occurs at the 5-phenyl group with formation of meta-nitro derivative, while under more severe conditions 3,5-dinitrobenzoic acid is obtained. 3-Oxy-5-phenyl-1H-1,2,3-triazole-4-carboxylic acid was also converted into the corresponding acid chloride and substituted amide.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 4, 2005, pp. 601–608.Original Russian Text Copyright © 2005 by Shtabova, Shaposhnikov, Mel’nikova, Tselinskii, Nather, Traulsen, Friedrichsen.     

Synthesis of 1,2,4- and 1,3,4-oxadiazoles from 1-aryl-5-methyl-1<Emphasis Type="Italic">H</Emphasis>-1,2,3-triazole-4-carbonyl chlorides

5-Substituted 2-(1-aryl-5-methyl-1H-1,2,3-triazol-4-yl)-1,3,4-oxadiazoles were synthesized by reaction of 1-aryl-5-methyl-1H-1,2,3-triazole-4-carbonyl chlorides with the corresponding 5-substituted 1H-tetrazoles. 5-Methyl-1-phenyl-1H-1,2,3-triazole-4-carbonyl chloride reacted with N′-hydroxybenzimidamides to give 3-aryl-5-(5-methyl-1-phenyl-1H-1,2,3-triazol-4-yl)-1,2,4-oxadiazoles. Reactions of 4-(5-methyl-1H-1,2,3-triazol-1-yl)benzoic acid with N′-hydroxybenzimidamides resulted in the formation of 3-aryl-5-[4-(5-methyl-1H-1,2,3-triazol-1-yl)phenyl]-1,2,4-oxadiazoles.     

Studies on 1,2,3-triazoles. Part XI. A new entry to the benzopyrano[2,3-D]-1,2,3-triazole system. Cyclization of 1-benzyl-5-chloro-4-(2-hydroxybenzoyl)-1H-1,2,3-triazoles

The acylation of simple arenes such as benzene and alkylated benzenes with N-protected 5-chloro-1H-1,2,3-triazole-4-carboxylic acid chlorides under Friedel-Crafts conditions results in excellent yields of the corresponding ketones. Resorcinol dimethyl ethers undergo similar acylation reactions in somewhat lower yield with concomitant monodemethylation, and these derivatives undergo a facile base mediated cyclization to 9-oxo-3H,9H-benzopyrano[2,3-d]-1,2,3-triazoles.     

Reactions of 1,2,3-Triazoles with Trifluoromethanesulfonyl Chloride and Trifluoromethanesulfonic Anhydride

Reactions of 4,5-dibromo-1,2,3-triazole, 1H-1,2,3-benzotriazole, and 2-phenyl-2H-1,2,3-triazole-4-carbonyl chloride with trifluoromethanesulfonyl chloride and trifluoromethanesulfonic anhydride were studied. 4,5-Dibromo-1,2,3-triazole sodium salt reacted with CF₃SO₂Cl in tetrahydrofuran to give 4,5-dibromo-2-(2-tetrahydrofuryl)-2H-1,2,3-triazole rather than expected 4,5-dibromo-2-trifluoromethylsulfonyl-2H-1,2,3-triazole. The latter was synthesized by treatment of 4,5-dibromo-1,2,3-triazole sodium salt with trifluoromethanesulfonic anhydride. The reaction of benzotriazole with (CF₃SO₂)₂O afforded 1-trifluoromethylsulfonyl-1H-1,2,3-benzotriazole and 1,2,3-benzotriazolium trifluoromethanesulfonate. 2-Phenyl-2H-1,2,3-triazole-4-carbonyl chloride reacted with trifluoromethanesulfonamide sodium salt in DMF, yielding N-(dimethylaminomethylene)trifluoromethanesulfonamide. Possible ways for formation of the unexpected products were proposed.     

Synthesis of 1-(1-aryl-1H-1,2,3-triazol-4-yl)-β-carboline derivatives

Reaction of 5-methyl-1-aryl-1H-1,2,3-triazole-4-carbocylic acid chlorides with tryptamine derivatives afforded substituted 1-aryl-N-[2-(1H-indol-3-yl)ethyl]-5-methyl-1H-1,2,3-triazole-4-carboxamides. At heating these compounds in toluene in the presence of POCl₃ and P₂O₅ Bischler-Napieralski cyclization occurs giving 1-(1-aryl-5-methyl-1H-1,2,3-triazol-4-yl)-4,9-dihydro-3H-β-carbolines that can be transformed into β-carboline and tetrahydro-β-carboline derivatives.     

Synthesis of 6-amino-1,2,3-triazolo[4,5-c] pyridin-4(5H)one (8-aza-3-deazaguanine) and 6-amino-1-(β-D-ribofuranosyl)-1,2,3-triazolo[4,5-c] pyridin-4(5H)one (8-Aza-3-deazaguanosine) via novel ring closure procedures

The total synthesis of 6-amino-1,2,3-triazolo[4,5-c]pyridin-4(5H)one (8-aza-3-deazaguanine, 3 ) and 6-amino-1-(β-D-ribofuranosyl)-1,2,3-triazolo[4,5-c]pyridin-4(5H)one (8-aza-3-deazaguano-sine, 22 ) has been described for the first time by a novel base-catalyzed ring closure of 4(5)-cyanomethyl-1,2,3-triazole-5(4)carboxamide (14) and methyl 5-cyanomethyl-1-(2,3,5-tri-O-ben-zoyl-β-D-ribofuranosyl)-1,2,3-triazole-4-carboxylate (17) , respectively. Under the catalysis of DBU, 2,4-dinitrophenylhydrazone of dimethyl 1,3-acetonedicarboxylate (7) was converted to methyl 5-methoxycarbonylmethyl-1-(2,4-dinitroanilino)-1,2,3-triazole-4-carboxylate (12) via dimethyl 2-diazo-3-iminoglutarate (8) . Catalytic reduction of 12 gave methyl 4(5)methoxycar-bonylmethyl-1,2,3-triazole-5(4)carboxylate (11) from which methyl 4(5)carbamoylmethyl-1,2,3-triazole-5(4)carboxylate (10) was obtained by ammonolysis. Dehydration of 10 provided methyl 4(5)cyanomethyl-1,2,3-triazole-5(4)carboxylate (13) which on amination gave 14 . The 1,2,3-triazole nucleosides 17, 18 and 19 were obtained from the stannic chloride-catalyzed condensation of the trimethylsilyl 13 and a fully acylated β-D-ribofuranose. The yield and ratio of the ribofuranosyl derivatives of 13 markedly depends on the ratio of stannic chloride used. The structures of the nucleosides 22 and 23 were established by a combination of NOE, ¹H-nmr and ¹³C-nmr spectroscopy.     

Efficient method for the synthesis of 1,2,3-triazole functionalized isoxazolidine derivatives by 1,3-dipolar cycloaddition of nitrones with terminal olefins

1-Phenyl-1,2,3-triazole-4-carbaldehyde 1 was treated with different N-alkyl hydroxylamine hydrochlorides 2 using NaHCO₃ to obtain 1,2,3-triazole substituted N-alkyl nitrones 3a–c. The nitrones 3a–c were further reacted with different substituted olefins and furnished 2-alkyl-3-(1-phenyl-1H-1,2,3-triazol-4-yl)-5-(substituted)isoxazolidine derivatives 4a–p in high yields via 1,3-dipolar cycloaddition reaction.     

Synthesis of [5-(1<Emphasis Type="Italic">H</Emphasis>-1,2,3-triazol-4-yl)-1,3,4-oxadiazol-2-yl]pyridines

2-, 3-, and 4-[5-(1-Aryl-5-R-1H-1,2,3-triazol-4-yl)-1,3,4-oxadiazol-2-yl]pyridines were synthesized from the corresponding 1-aryl-5-R-1H-1,2,3-triazole-4-carbonyl chlorides and 2-, 3-, and 4-(1H-tetrazol-5-yl)-pyridines.     

Reactions of 2-benzylidenemalononitrile and 2-nitro-3-phenylacrylonitrile with aryl azides

Reactions of 2-benzylidenemalononitrile and 2-nitro-3-phenylacrylonitrile with aryl azides in diethyl ether at room temperature gave mixtures of regioisomeric 1(3)-aryl-5-phenyl-4,5-dihydro-1(3)H-1,2,3-triazole-4,4-dicarbonitriles and 1-aryl-5(4)-phenyl-1H-1,2,3-triazole-5(4)-carbonitriles, respectively. 2-Benzylidenemalononitrile reacted with the same arylazides on heating in boiling chloroform to produce 1-aryl-2-phenylaziridine-2,2-dicarbonitriles.     

Synthesis of novel heterocycles using 1,2,3-triazole-4-carbohydrazides as precursors

Herein, we report the synthesis of various heterocyclic ring systems containing 1,2,3-triazole from the reactions of acid hydrazides and commercially available reagents, using efficient and simple procedures. Reactions of certain 1,2,3-triazole-4-carbohydrazides and α-bromoketones in boiling ethanol afforded the corresponding hydrazones rather than the expected triazines. The hydrazones could also be synthesized in 85-90% yield via an alternative pathway that involved the reaction of 1,2,3-triazole-4-carbohydrazides and 4-acetyl-1,2,3-triazoles in boiling ethanol containing glacial acetic acid. Reaction of one of the 4-carbohydrazides with carbon disulfide, followed by the reaction with hydrazine hydrate, gave 4H-1,2,4-triazole-3-thiol in 73% yield, which further reacted with other α-bromoketones in boiling ethanol to afford 7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazines in 82-84% yields. Additionally, reactions of certain carbohydrazides with ethyl 2-cyano-3,3-bis(methylthio)acrylate gave 1-aryl-1H-1,2,3-triazole-4-carbohydrazides rather than the expected 1H-pyrazole-4-carboxylates.     

Hydrothermal syntheses and crystal structures of two Zn(II) complexes with 1-substituted-1H-[1,2,3]-triazole-4-carboxylic acid

Two new Zn(II) complexes, [Zn(L)₂(H₂O)₂] where L is 1-substituted 5-methyl-1H-[1,2,3]-triazole-4-carboxylic acid, have been synthesized and characterized by elemental analysis, FT–IR, and solid-state fluorescent emission spectroscopy. Structures have been established by single-crystal X-ray diffraction, revealing the discrete nature of the complexes in which Zn centers adopt slightly distorted octahedral geometry. In the complexes, the 1-substituted 5-methyl-1H-[1,2,3]-triazole-4-carboxylic acid is bidentate.     

An improved procedure for the preparation of 1-benzyl-1H-1,2,3-triazoles from benzyl azides

A procedure for the preparation of substituted 1-benzyl-1H-1,2,3-triazoles from benzyl azides under very mild conditions is described. The method provides improved yields and extends the scope of the Dimroth Reaction to other types of active methylene compound to those previously used. Benzyl azides react with active methylene compounds in dimethyl sulphoxide catalysed by potassium carbonate at 35–40° to give 1H-1,2,3-triazoles usually in good yield. Acetonitrile derivatives gave 5-amino-1H-1,2,3-triazoles whereas diethyl malonate gave 5-hydroxy-1H-1,2,3-triazoles. 1H-1,2,3-Triazole-4-carboxylate esters and 1H-1,2,3-triazole-4-ketones were obtained from ethyl acetoacetate and β-diketones respectively. Benzyl methyl ketone reacted to give a 5-methyl-4-phenyl-1H-1,2,3-triazole, but acetone and acetophenone failed to react. Other active methylene compounds which did not react under these reaction conditions included ethyl cyanoacetate, ethyl fluoroacetate and ethyl nitroacetate.     

ZnO nanoparticles-mediated regioselective synthesis of methyl-N-alkylated 1,2,3-triazole-4-carboxylates

The 1,2,3-triazoles are versatile synthetic intermediates of many biologically active compounds, and their N-1 substituted analogues are potential pharmaceutically important derivatives. In this study, an efficient regioselective N-alkylation reaction of methyl-1H-1,2 3-triazole-4-carboxylate 3 with alkyl halides 4 catalyzed by ZnO nanoparticles in the presence of potassium hydroxide as base and DMSO as solvent is reported which leads to methyl N ₁-alkylated 1,2,3-triazole-4-carboxylates 5 in good yields.     

两种1,2,3-三唑衍生物的配合物合成策略:晶体结构和表面分析

在不同反应条件下反应得到了两种1,2,3-三唑衍生物的配合物[Co（H₂O）₆][Co（L¹）₃]₂·4H₂O（1）和Cu（L²）₂（2）（HL¹=5-methyl-1-phenyl-1H-1,2,3-triazole-4-carboxylic acid;HL²=1-（4-iodophenyl）-5-methyl-1H-1,2,3-triazole-4-carboxylic acid）。通过X射线单晶衍射和红外光谱确定了晶体结构,同时对配合物1和2进行了表面作用分析（Hirshfeld surface analysis）,在二维指纹图谱中可以清楚的看到配合物中的主要分子间作用。     

Reaction of 1-Aryl-1H-1,2,3-Triazole-4-Carbonyl Chlorides/Isothiocyanates with 3-Amino-5-Methylisoxazole

Abstract

1-Aryl-1H-1,2,3-triazole-4-carbonyl chlorides were selected as starting materials for the Boulton–Katritzky rearrangement. When 3-amino-5-methylisoxazole was acylated by 1-aryl-1H-1,2,3-triazole-4-carbonyl chlorides, 1-aryl-5-methyl-N-(5-methylisoxazol-3-yl)-1H-1,2,3-triazole-4-carboxamides 5 were obtained and no further rearrangement occurred. On the other hand, when 1-aryl-1H-1,2,3-triazole-4-carbonyl chlorides were first converted into isothiocyanates by the reaction with KSCN and then were allowed to react with 3-amino-5-methylisoxazole 4 in one pot, intermediate thioureas were formed and spontaneously transformed in statu nascendi into 1,2,4-thiadiazole derivatives 6.

GRAPHICAL ABSTRACT      

Trifluoromethanesulfonic Hydrazides

We succeeded to observe at low temperature in reactions of trifluoromethanesulfonic anhydride and trifluoromethanesulfonyl chloride with hydrazine, phenyl hydrazine, and 1,1-dimethylhydrazine a formation of the corresponding trifluoromethanesulfonic hydrazides that at heating to room temperature decomposed liberating nitrogen and affording trifluoromethanesulfinic acid. 2-Phenyl-2H-1,2,3-triazole-4-carboxylic hydrazide reacted with trifluoromethanesulfonic anhydride to furnish trifluoro-N'-(2-phenyl-2H-1,2,3-triazol-4-ylcarbonyl)methane-sulfonic hydrazide that decomposed at heating with elimination of trifluoromethanesulfinic acid and nitrogen yielding 2-phenyl-2H-1,2,3-triazole-4-carbaldehyde.     

1,3-dipolar cycloaddition of trimethylsilyl azide to propynals and dimerization of 1<Emphasis Type="Italic">H</Emphasis>-1,2,3-triazole-5-carbaldehydes to tricyclic bis-hemiaminals

Reactions of trimethylsilyl azide with 3-trimethylsilyl-2-propynal and 2-propynal were studied. X-Ray analysis of the molecular structure of 4-trimethylsilyl-1H-1,2,3-triazole-5-carbaldehyde showed that the carbonyl group appears in the s-cis conformation with respect to the double C=C bond in the heteroring. The effect of the temperature and polarity of the medium on the ability of 1H-1,2,3-triazole-5-carbaldehyde to undergo dimerization to tricyclic bis-hemiaminals was examined by IR and ¹H NMR spectroscopy.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 12, 2004, pp. 1852–1857.Original Russian Text Copyright © 2004 by Demina, Novopashin, Sarapulova, Larina, Smolin, Fundamenskii, Kashaev, Medvedeva.     

Transaminations of enaminones:A Synthesis of tricyclic,N-aryl, 1,2,3-triazole-fused pyridones

1-Phenylmethyl- and 1-(4-methoxyphenylmethyl)-5-chloro-1,2,3-triazole-4-carbonyl chlorides acylated the pyrrolidine enamines of cyclopentanone and cyclohexanone, and the resulting enaminones underwent transaminations with aryl amines under acidic conditions. The products then cyclized under basic conditions to linearly fused, tricyclic 3-phenylmethyl- and 3-(4-methoxyphenylmethyl)-4-aryl-8-oxo-4,5,6,7-tetrahydrocyclopenta[6]-1,2,3-triazolo[4,5-e]pyridines, and to 5,6,7,8-tetrahydro-4-aryl-3H-1,2,3-triazolo[4,5-b]quinolin-9(4H)-ones. Similar transaminations afforded the related 8-phenyl- and 8-(3-chlorophenyl)-1,5,7,8-tetrahydro-1-(phenylmethyl)-4H-thieno[3,4-e]-1,2,3-triazolo[4,5-b]pyridin-4-ones. Phase-transfer and catalytic hydrogenolyses of some of these intermediates furnished 4-aryl-8-oxo-4,5,6,7-tetrahydrocyclopenta[b]-1,2,3-triazolo[4,5-e]pyridines and 4-aryl-5,6,7,8-tetrahydro-3H,2,3-triazolo[4,5-b]quinoline-9-(4H)-ones. The 3-(4-methoxyphenylmethyl)-4-aryl intermediates were sterically crowded. Two protons from the methoxyphenylmethylphenylmethylgroups were dramatically shielded because of anisotropic effects exerted by the 4-aryl substituents.     

Design,synthesis, and anticancer activity evaluation of novel aziridine-1,2,3-triazole hybrid derivatives

Some new 1-aryl-4-[(aziridine-1-yl)diaryl-methyl]-5-methyl-1H-1,2,3-triazole derivatives 7j–s were synthesized by the one-pot reaction of diaryl-(1-aryl-5-methyl-1H-1,2,3-triazol-4-yl)methanol compounds 6j–s formed from 1-aryl-5-methyl-1H-1,2,3-triazole-4-carboxylic acid derivatives. The new compounds 7j–s and 6j–s are investigated by ¹H and ¹³C NMR, MS, and IR. The anticancer activity of the synthesis target compounds was evaluated against human leukemia (HL-60) cells and human hepatoma G2 cells. Some of the compounds were highly efficient. The ¹H-NMR signals of the aziridine-ring cis-H/trans-H protons were found to be two group peaks at 1.800–1.884 and 1.183–1.327?ppm.     

Methyl 3-cyclopropyl-3-oxopropanoate in the synthesis of heterocycles having a cyclopropyl substituent

Reactions of methyl 3-cyclopropyl-3-oxopropanoate with chloroacetone and ammonia, benzaldehyde and ammonia, and benzoquinone gave, respectively, methyl 2-cyclopropyl-5-methyl-1H-pyrrole-3-carboxylate, dimethyl 2,6-dicyclopropyl-4-phenyl-1,4-dihydropyridine-3,5-dicarboxylate, and methyl 2-cyclopropyl-5-hydroxy-1-benzofuran-3-carboxylate. Cyclization of methyl 3-cyclopropyl-3-oxopropanoate with ethyl chloro(arylhydrazono)ethanoates and other halohydrazones led to the formation of 3-substituted 1-aryl-5-cyclopropyl-1H-pyrazole-4-carboxylic acids, and 5-cyclopropyl-1-(quinolin-5-yl)-1H-1,2,3-triazole-4-carboxylic acid was obtained by reaction of the title compound with 5-azidoquinolines.