The 1-alkoxy-6-nitro-1,2,3-benzotriazole system

The 1-alkoxy-6-nitro-1,2,3-benzotriazole system has been synthesized and characterized via its physical and chemical properties. INDO/molecular orbital calculations provide a good account of the major bands in its ultraviolet absorption spectrum.     

The 1-alkoxy-1,2,3-benzotriazole system

The 1-alkoxy-1,2,3-benzotriazole system has been synthesized and defined on the basis of its physical and spectral properties. Bond orders and charge densities of the parent compound in the series 1-methoxy-1,2,3-benzotriazole have been calculated. All-valence-electron calculations with configuration interaction give a reasonable account of the observed absorption spectrum.     

The 5-chloro-1-alkoxy-1,2,3-benzotriazole system

The 5-chloro-1-alkoxy-1,2,3-benzotriazole system has been synthesized and characterized via its physical and chemical properties. HMO calculations predict the most reactive sites on the molecule.     

The 1-alkoxy-4,5-dichloro-1,2,3-benzotriazole system

The 1-alkoxy-4,5-dichloro-1,2,3-benzotriazole system has been synthesized and characterized via its physical and chemical properties. INDO/S MO calculations provide a good account of the ultraviolet absorption spectrum.     

The photolysis of 1-benzyloxy-1,2,3-benzotriazole

1-Benzyloxy-1,2,3-benzotriazole was photolyzed and found to yield benzaldehyde and azobenzene as the principal products.     

The synthesis of the 1- and 2-cycloalkyl-1,2,3-benzotriazole system

The first reported synthesis of 1- and 2-cycloalkyl-1,2,3-benzotriazoles is reported. Physical and spectral data of the system are reported. Molecular orbital calculations on the 1,2,3-benzotriazole anion show that N₁ is a more nucleophilic site than N₂.     

The photolysis of the l-cycloalkoxy-5-chloro-1,2,3-benzotriazole system

Three l-cycloalkoxy-5-chloro-1,2,3-benzotriazoles were photolyzed at 254 nm. The major photolytic pathway yielded the corresponding cyclic ketone and 4,4′-dichloroazobenzene.     

Selective synthesis of 1,3-dialkyl-4-nitro-1,2,3-triazolium salts from 1-alkyl-4-nitro-1,2,3-triazoles and dialkyl sulfates

The process of alkylation of 1-alkyl-substituted 4-nitro-1,2,3-triazoles with dimethyl and diethyl sulfates has been studied. The structures of the N,N’-dialkyl-C-nitro-1,2,3-triazolium alkylsulfates and perchlorates has been confirmed by IR, ¹H and ¹³C NMR spectroscopy. Alkylation with an excess of dialkyl sulfate occurred regioselectively at N-3 with the formation of 1,3-dialkyl-4-nitro-1,2,3-triazolium salts, which is in agreement quantum-chemical calculations of the relative stability of the corresponding isomeric cations. The molecular and crystal structures of the first example of this type of salt – 1,3-diethyl-4-nitro-1,2,3-triazolium perchlorate – have been determined by X-ray crystallo-graphy. Nitrotriazolium salts with mixed alkyl substituents – 3-ethyl-1-methyl- and 1-ethyl-3-methyl-4-nitro-1,2,3-triazolium salts – have been synthesized an studied for the first time.     

Synthesis of 4-Aryl-5-nitro-1,2,3-triazoles

Russian Journal of Organic Chemistry -     

4-甲基-5-硝基-1,2,3-连三唑的合成

以丙二酸二乙酯为原料,经水解、硝化得到关键中间体偕二硝基乙酸乙酯(2);2与乙醛、叠氮化钠缩合环化得到4-甲基-5-硝基-1,2,3-连三唑(3)。3的结构经NMR,IR和元素分析表征。初步探讨了硝化反应的反应历程,并对制备2的合成进行了工艺改进,发现以NaNO2-98%HNO3为硝化试剂的新方法,2的收率达62.1%,纯度93.1%。     

Alkylation of 1,2,3-benzotriazole with iodomethyl ketones

Solvent-free reactions of 1,2,3-benzotriazole with 1-iodopropan-2-one and 1,3-diiodopropan-2-one in the absence of a catalyst involved alkylation of the heteroring at the N¹ atom and subsequent quaternization at the N³ atom with formation of 1,3-bis(2-oxopropyl)-1H-1,2,3-benzotriazolium triiodide which is a new conducting ionic liquid. The reaction of 1,2,3-benzotriazole with 1,3-diiodopropan-2-one was accompanied by reductive deiodination of the iodomethyl groups in the initial ketone with hydrogen iodide liberated by N¹-alkylation. Triiodide ion readily exchanges for nitrate ion by the action of AgNO₃ to produce 1,3-bis(2-oxopropyl)-1H-1,2,3-benzotriazolium nitrate. The reaction of 1,2,3-benzotriazole with 2-iodo-1-phenylethan-1-one in melt resulted in the formation of 1,3-bis(2-oxo-2-phenylethyl)-1H-1,2,3-benzotriazolium triiodide.     

N-Alkylation of 4-nitro-1,2,3-triazole revisited. Detection and characterization of the N3-ethylation product, 1-ethyl-5-nitro-1,2,3-triazole

The products of the alkylation of sodium 4-nitro-1,2,3-triazolate with ethyl bromide were investigated using ¹H, ¹³C, and ¹⁵N NMR spectroscopy. It was found that alkylation proceeds on the triazole nitrogen atoms giving a mixture of three isomeric N-ethyl-4-nitro-1,2,3-triazoles. The molar ratio of N1, N2, and N3-alkylation products was 4:8:1. The formation of a minor N3-isomer, namely 1-ethyl-5-nitro-1,2,3-triazole was confirmed by X-ray structural analysis of single crystals of its tetranuclear copper(II) complex obtained by reaction of copper(II) chloride dihydrate with a mixture of the N2 and N3-isomers.     

Asymmetric oxidation of 4-nitro-6-trifluoromethyl-1,2,3-benzotrithiole

Both enantiomers of 4-nitro-6-trifluoromethyl-1,2,3-benzotrithiole 1-oxide as analogs of Varacins B and C were synthesized for the first time. The use of the Modena method ensures higher optical purity but lower yields of the chiral sulfoxides, as compared to the Kagan procedure.     

Reactions of 2,4-disubstituted 5-nitro-1,2,3-triazole 1-oxides. 2. Oxidation of 2-substituted 4-amino(alkylamino)-5-nitro-1,2,3-triazole 1-oxides

The oxidation of substituted aminonitrotriazole oxides to the corresponding dinitro derivatives of triazole and azotriazole oxides has been studied. Communication 1, see ref. [1]. N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow, Russia; e-mail: cheminst@mail.psu.ru. Institute of Chemical Physics at Chernogolovka, Russian Academy of Sciences, 124432 Chernogolovka, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1356–1362, October, 1999.     

Synthesis of 5-alkoxy-3-amino-7-nitro-1,2,4-benzotriazine 1-oxides from 1,3,5-trinitrobenzene

1-Alkoxy-3,5-dinitrobenzenes were nitrated to give 1-alkoxy-2,3,5-trinitrobenzenes. The reaction of the latter with guanidine affordsN-(2-alkoxy-4,6-dinitrophenyl)guanidines, which undergo cyclization under the action of KOH to form 5-alkoxy-3-amino-7-nitro-1,2,4-benzotriazine 1-oxides. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1650–1652, September, 2000.     

Solvent extraction of Zn/II/ with 1,2,3-benzotriazole into n-hepatanol

A method based on solvent extraction has been developed for the radiochemical separation of Zn/II/ from other elements employing 1,2,3-benzotriazole as a complexing agent and n-heptanol as an extractant. Optimum conditions for the extraction have been established. The effect of various anions and cations on the extraction coefficient value of Zn/II/ has been studied. The stoichiometry of the metal to reagent determined by the method of substoichiometric extraction and slope-ratio method was found to be 12.