Electrophilic substitution of thetert-butyl-NNO-azoxy group by the bromine atom

The electrophilic substitution of thetert-butyl-NNO-azoxy group by the bromine atom was observed for the first time when 6-bromo-2,4-bis(tert-butyl-NNO-azoxy)-5-chloro-1,3-phenylenediamine was treated with bromine in AcOH. The structural factors promoting this reaction are discussed. The direction of the replacement was confirmed by PM3 calculations of the heats of formation of intermediate cationic σ-adducts. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2131–2134, November, 1999.     

Synthesis of 1-aryl-2-alkenyldiazene 1-oxides

1-Aryl-2-alkenyldiazene 1-oxides were prepared by the reactions of 1-aryl-2-bromodiazene 1-oxides with olefins followed by dehydrobromination of the intermediate 1-aryl-2-(-bromoalkyl)diazene 1-oxides by triethylamine.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 924–927, May, 1995.This work was carried out at the Scientific Educational Center of the Institute of Organic Chemistry of the RAS with financial support of the Russian Foundation for Basic Research (Project No. 93-03-18461).     

Reaction of 1-aryl-2-alkenyldiazene 1-oxides with hydrogen chloride. Novel approach to the synthesis of functionally substituted arylhydrazones

The reaction of 1-aryl-2-alkenyldiazene 1-oxides with HCl yields arylhydrazones of -chloroacyl chlorides, which eliminate HCl to give 1-aryl-2-(1-chloroalken-1-yl)diazenes. The latter add amines, alcohols, and carboxylic acids to give arylhydrazone chlorides with -functional groups.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 928–933, May, 1995.The work was carried out at the Scientific Educational Center of the Institute of Organic Chemistry of the RAS with financial support of the Russian Foundation for Basic Research (Project No. 93-03-18461).     

Dinitramide and its salts

Dinitramide readily adds to acrolein, methyl vinyl ketone, and phenyl vinyl ketone, but not to acrylonitrile or methyl acrylate. Treatment of dinitro compounds (O₂N)₂NCH₂CH₂COR (R = H, Me, Ph, OMe) with bases results in dinitramide salts in 66–83 % yields.For part 1, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1264–1266, July, 1994.     

Chemistry of beta-functionalized alpha-nitroso ethylenes. Methyl beta-nitroso acrylate as heterodienophile in

[formula: see text] beta-Functionalized nitroso alkene 2, obtained from methyl beta-nitropropionate 1 and N,O-bis(trimethylsilyl)acetamide, can function as a good heterodienophile in Diels-Alder reactions. Therefore, 2 was trapped by cyclic dienes to give adducts 4 with the corresponding stereoselectivity. Cycloadduct 4a undergoes retro-[4 + 2]-cycloaddition at 33 degrees C in solution; thus 4a can be used to generate nitroso alkene 2 in neutral medium. Cyclopentadiene reacts with adduct 4a according to an endo-(4 + 2]-cycloaddition scheme to give cycloadduct 5 in low yield.     

Annulated benzotetrazine 1,3-dioxides 1. [1,2,5]Oxadiazolo[3,4-f][1,2,3,4]benzotetrazine 2,4,7-and 2,4,9-trioxides

Thermolysis of 6-azido-5-nitro-7-R-benzotetrazine 1,3-dioxides (R = H and Br) gave benzotetrazine 1,3-dioxides annulated with the furoxan ring at the C(5)-C(6) bond. According to the NMR data, these compounds at 297 K are equilibrium mixtures of two isomers with different positions of the N-oxide oxygen atom in the furoxan ring. Full assignment of signals in the ¹³C NMR spectra of the compounds obtained was accomplished. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 133–136, January, 2006.     

Trifluoromethylation and pentafluorophenylation of enamines

A reaction of enamines with Me₃SiCF₃ and Me₃SiC₆F₅ in the presence of carboxylic acids leading to α-CF₃-and α-C₆F₅-substituted amines has been studied. 3-Cyanobenzoic acid was found to be the optimal promoter of these reactions. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1466–1468, August, 2007.     

Synthesis of β-nitroxyalkylnitramines

β-Nitroxyalkylnitramines were obtained by nitration of β-hydroxyalkyl sulfamates, products of the condensation of derivatives of sulfamic acid with alkene oxides, by a mixture of HNO₃ and H₂SO₄. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1061–1062, May, 1997.     

Spectroscopic investigation of 2-nitrodiazenoxides

2-Nitrodiazenoxides have been studied by vibrational spectroscopy methods. The main regularities of the changes in the stretching vibration frequencies of the nitro and diazenoxide groups were studied as functions of different factors.X-ray data for compounds2 and3 will be reported later.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1771–1774, October, 1994.This work was carried out with financial support from the Russian Foundation for Basic Research (Project No 93-03-18461).     

Synthesis of 1,3,5-trisubstituted 1,2,4-triazolio-4-nitroimides

A method for the synthesis of 1,3,5-trisubstituted 1,2,4-triazolio-4-nitroimides was developed. The method is based on the alkylation of the corresponding salts of 3,5-disubstituted 4-nitramino-1,2,4-triazoles.