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.     

Trifluoromethyl Sulfones and Perfluoroalkanesulfonamides of the Azole Series

2-Phenyl-4-trifluoromethylsulfonylmethyl-2H-1,2,3-triazole was synthesized from 4-bromo-methyl-2-phenyl-2H-1,2,3-triazole and sodium trifluoromethanesulfinate CF₃SO₂Na. 1(2)-Ethyl-4-nitro-1(2)H-1,2,3-triazoles and 4-nitro-2-phenyl-2H-1,2,3-triazole were reduced to the corresponding amines. Intermediate 1,2-bis(1-ethyl-1H-1,2,3-triazol-4-yl)diazene 1-oxide exists as a mixture of syn and anti isomers, the former being stabilized via formation of a strong intramolecular hydrogen bond. The reduction of 2-ethyl-4-nitro-2H-1,2,3-triazole in the presence of HCl afforded the target 4-amino-2-ethyl-2H-1,2,3-triazole and also 4-amino-5-chloro-2-ethyl-2H-1,2,3-triazole. Treatment of alkyl-substituted 4-amino-1,2,3-triazoles with trifluoromethanesulfonyl chloride and pentafluoroethanesulfonyl chloride gave N-triazolyl-substituted trifluoromethane- and pentafluoroethanesulfonamides and -imides.     

Reaction of <Emphasis Type="Italic">N</Emphasis>-Sulfinyltrifluoromethanesulfonamide CF<Subscript>3</Subscript>SO<Subscript>2</Subscript>N=S=O with Carbonyl Compounds

N-Sulfinyltrifluoromethanesulfonamide CF₃SO₂N=S=O reacts with salicylaldehyde, 2-furaldehyde, 2-thiophenecarbaldehyde, 3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde, and 2-phenyl-2H-1,2,3-triazole-4-carbaldehyde to afford the corresponding N-aryl(hetaryl)methylidenetrifluoromethanesulfonamides in high yields. Reactions of the latter with aniline give no adducts at the C=N bond but transamination products. The reaction of trifluoromethanesulfonamide with phenyl isocyanate led to formation of N,N′-diphenylurea instead of expected N-phenyl-N′-(trifluoromethylsulfonyl)urea.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1006–1010.Original Russian Text Copyright © 2005 by Shainyan, Tolstikova.     

Synthesis and structure of <Emphasis Type="Italic">N</Emphasis>-(diaminomethylidene)- and <Emphasis Type="Italic">N</Emphasis>-[bis(cyclohexylamino)methylidene]trifluoromethanesulfonamides

N-Trifluoromethylsulfonyl-substituted guanidines CF₃SO₂N=C(NHR)₂ (R = H, cyclohexyl) were synthesized in nearly quantitative yield by reactions of N-sulfinyltrifluoromethanesulfonamide CF₃SO₂N=S=O with urea and of trifluoromethanesulfonamide with N,N′-dicyclohexylcarbodiimide. N-[Bis(cyclohexylamino)-methylidene]trifluoromethanesulfonamide was subjected to protonation with trifluoromethanesulfonic acid and bis(trifluoromethanesulfonyl)imide, and the structure of the resulting salts and initial N-trifluoromethylsulfonylguanidines was studied by NMR and IR spectroscopy and DFT quantum-chemical calculations.     

Reaction of γ-dicarboxylic acids amides and imides with trifluoromethanesulfonamide and formaldehyde

Three-component condensation of trifluoromethanesulfonamide with paraformaldehyde and succinamide depending on the reaction conditions led alongside bis(trifluoromethanesulfonamido)methane to the formation of a substitution product, bis[(trifluoromethylsulfonyl)aminomethyl]succinamide, or to a cyclization product, N-[trifluoromethylsulfonyl)aminomethyl]succinimide. The attempt to obtain the latter by the reaction of the trifluoromethanesulfonamide sodium salt CF₃SO₂NHNa with N-chloromethylsuccinimide unexpectedly resulted in N,N-bis(succinimidomethyl)-trifluoromethanesulfonamide. Analogously the reaction of CF₃SO₂NHNa with N-chloromethyl-phthalimide gave N,N-bis(phthalimidomethyl)trifluoromethanesulfonamide. The reaction of CF₃SO₂NHNa with succinimide and phthalimide in water and alcohol solution resulted in the ring opening and further transformation of the formed monosubstituted N-(trifluoromethylsulfonyl)amides of succinic and phthalic acids.     

2-Azido-1,3,4-thiadiazoles, 2-Azido-1,3-thiazoles,and Aryl Azides in the Synthesis of 1,2,3-Triazole-4-carboxylic Acids and Their Derivatives

Diazotization of 2-amino-1,3,4-thiadiazoles gave 1,3,4-thiadiazole-2-diazonium sulfates which were converted to 2-azido-1,3,4-thiadiazoles. The latter reacted with ethyl acetoacetate in the presence of sodium methoxide in methanol to produce 1-(5-R¹-1,3,4-thiadiazol-2-yl)-5-R²-1H-1,2,3-triazole-4-carboxylic acid derivatives. The reactions of 2-azido-5-methyl-1,3,4-thiadiazole and 2-azido-1,3-thiazole with ethyl 3-(1,3-benzodioxol-5-yl)-3-oxopropanoate led to the formation of 1,2,3-triazole ring under milder conditions (K₂CO₃, DMSO). Various 1,2,3-triazole-4-carboxylic acid derivatives were synthesized.     

Functional Acetal Methacrylates: IV. Electrophophilic Addition of Triazoles to Vinyloxyalkyl Methacrylates

Reactions of vinyloxyalkyl methacrylates with triazoles (1,2,4-triazole, 1,2,3-benzotriazole, 5-methyl-1,2,3-benzotriazole) under electrophilic conditions (50°C, 1-2 h, 1 wt% CF₃COOH) occur chemoselectively and afford in quantitative yield polyfunctional methacrylates with triazole and benzotriazole yields.     

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.     

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.     

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.     

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 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.     

Polyfluoroalkyl <Emphasis Type="Italic">N</Emphasis>-(trifluoromethylsulfonyl)amidosulfites,number one stable NH-containing amidosulfites

We prepared for the first time NH-containing amidosulfites, polyfluoroalkyl N-(trifluoro-methylsulfonyl) amidosulfites CF₃SO₂NHS(O)OR_F, by reaction of N-sulfinyl-trifluoromethanesulfonamide CF₃SO₂N=S=O with alcohols R_FOH. Amidosulfites were formed also in reaction of chlorosulfites R_FOS(O)Cl with trifluoromethanesulfonamide, with its sodium salt, and N-trimethylsilyl derivative.     

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.     

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.     

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。     

Pyrolysis and photolysis of 1-aroylamino-4,5-diaryl-1,2,3-triazoles: Generation and thermal transformations of 4,5-diaryl-1,2,3-triazolyl radicals

The pyrolysis of 1-aroylamino-4,5-diphenyl-1,2,3-triazoles 1 yields, pressumably via the 4,5-diphenyl-1,2,3-triazolyl radical ( 2a ), 2,3-diphenyl-2H-azirine ( 11a ) and 2-aryl-4,5-diphenylimidazoles 14 as the major products. Upon irradiation 1-benzoylamino-4,5-diphenyl-1,2,3-triazole ( 1a ) gives 4,5-diphenyl-1 (2)H-1,2,3-triazole ( 4a ) via the 1,2,3-triazolyl radical 2a , together with benzamide ( 5a ) and 1,2-bisbenzoylhydrazine ( 6a ). Products 5a and 6a result from the benzoylamino radical 3a by hydrogen atom abstraction and dimerization respectively.     

Synthesis and single-crystal X-ray diffraction studies of 1-β-D-ribofuranosyl-1,2,4-triazole-3-sulfonamide and certain related nucleosides

1-β-D-Ribofuranosyl- 21 , 1-(2-deoxy-β-D-erytftro-pento fur anosyl)- 27 and 1-β-D-arabinofuranosyl- 29 derivatives of 1,2,4-triazole-3-sulfonamide ( 19 ) have been prepared. Glycosylation of the silylated 19 with 1,2,3,5-tetra-0-acetyl-β-D-ribofuranose ( 5 ) in the presence of trimethylsilyl triflate gave the corresponding blocked nucleoside ( 20 ), which on ammonolysis afforded 1-β-D-ribofuranosyl-1,2,4-triazole-3-sulfonamide ( 21 ). Stereospecific glycosylation of the sodium salt of 19 with either 1-chloro-2-deoxy-3,5-di-O-p-toluoyl-α-D-erythro-pentofuranose ( 22 ) or 1-chloro-2,3,5-tri-0-benzyl-α-D-arabinofuranose ( 23 ) provided the corresponding protected nucleosides 26 and 28. Deprotection of 26 and 28 furnished 1-(2-deoxy-β-D-erythro-pentofuranosyl)-1,2,4-triazole-3-sulfonamide ( 27 ) and 1-β-D-arabinofuranosyl-1,2,4-triazole-3-sulfonamide ( 29 ), respectively. 2-0-D-Ribofuranosyl-1,2,4-triazole-3(4H)-thione ( 7 ) and 4-β-D-ribofuranosyl-1,2,4-triazole-3(2H)-thione ( 9 ) were also prepared utilizing either an acid catalyzed fusion of 1,2,4-triazole-3(1H,2H)-thione ( 4 ) with 5 , the reaction of 5 with silylated 4 in the presence of trimethylsilyl triflate, or by ring closure of 4-(2,3,5-tri-0-benzoyl-β-D-ribofuranosyl)thiosemicarbazide ( 10 ) with mixed anhydride and subsequent deacylation. The synthesis of 1-β-D-ribofuranosyl-3-benzylthio-1,2,4-triazole ( 15 ) has also been accomplished by the silylation procedure employing 3-benzylthio-1,2,4-triazole ( 13 ) and 5 to give 1-(2,3,5-tri-0-acetyl-β-D-ribofuranosyl)-3-benzylthio-1,2,4-triazole ( 14 ). Deacetylation of 14 furnished 15 . The structural assignments of 7, 14 and 21 were made by single-crystal X-ray diffraction analysis and their hydrogen bonding characteristics have been studied. The sulfonamido-1,2,4-triazole nucleosides are devoid of any significant antiviral or antitumor activity in cell culture.     

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      

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.