V. A. Ogurtsov

Reaction of furoxanenitrolic acids with nitrogen tetroxide

It has been found that the main direction of the reaction of furoxanenitrolic acids with N2O4 is the formation of the corresponding nitrile oxides and their subsequent conversions.

SYNTHESIS OF FURAXANENITROLIC ACIDS

Previously unreported furoxanenitrolic acids have been synthesized.

14N NMR spectroscopy of nitrofuroxans-qualitative and quantitative method for their determination

For the first time, the14N NMR spectra of nitrofuroxans were investigated, and it was shown that the14N signals are narrow; this allows this method to be utilized analytically. Taking the example of nitrochlorofuroxan, the unusual rearrangement of the 4-nitro isomer to the 3-nitro isomer was found.

Syntheses with nitrile oxides. 2. Reaction of aromatic nitrile oxides with bis(trimethylsilylcarbodiimide)

The reaction of aromatic nitrile oxides with bis(trimethylsilylcarbodiimide) gives 5-amino-3-aryl-1,2,4-oxadiazoles.

Syntheses based on nitrile oxides. 1. Reaction of aromatic nitrile oxides with N-cyanimides

The reaction of trialkylaminocyanimides with aromatic nitrile oxides leads to trialkylamino-(3-aryl-1,2,4-oxadiazol-5-yl)imides, while the corresponding reactions with sulfylcyanimines and phosphincyanimides do not take place. Using x-ray structural analysis the principal structural features of the 1,2,4-oxadiazole products have been elucidated.

Unusual transformation of 3-alkylfuroxans into 3-(nitrooxyalkyl)furoxans on treatment with a mixture of nitric and sulfuric acids

A versatile one-pot synthesis of 4-substituted 3-(nitrooxyalkyl)furoxans by the reaction of 3-alkylfuroxans with a mixture of nitric and sulfuric acids was developed. A plausible mechanism of this unusual transformation was explained in terms of a new Grob-type fragmentation.

Unexpected and Rich Chemistry of 4,5-Dichloro-1,2-dithiole-3-thione

Abstract 4,5-Dichloro-1,2-dithiole-3-thione was found to undergo 1,3-dipolar cycloaddition reactions with internal and terminal alkynes. The combination of these reactions together with new transformations afforded versatile heterocyclic systems including 1,3-dithioles, imino-1,3-dithietanes, 2-iminothiophen-3-ones, thienothiopyranthiones, and others.

Reactions of nitrile oxides with nitrogen oxides. 2. Reactions with nitrogen monoxide and nitrogen sesquioxide

We have studied the reactions of aromatic nitrile oxides with nitrogen monoxide and nitrogen sesquioxide. It was shown that nitrogen monoxide removes an oxygen atom from the nitrile oxide with formation of the corresponding nitrile and nitrogen dioxide. The reaction products with nitrogen sesquioxide are formed as a result of reactions of the nitrile oxide with nitrogen monoxide and nitrogen tetroxide.

NMR spectra and structure of 4,7-dimethylpyridazino[4,5-c]furoxane N,N′-dioxide

ConclusionsNMR spectroscopy was used to confirm the structure of 4,7-dimethylpyridazino[4,5]furoxane N,N′-dioxide obtained by the oxidation of diacetylfuroxane dioxide by nitrogen tetroxide.

Synthesis of 1-[(1,2-dithiol-3-ylidene)methyl]pyrrolo[1,2-a]pyrazines and 2-[(1,2-dithiol-3-ylidene)methyl]pyridines from 1,2-dithiole-3-thiones

Benzo- and pyridoannulated 1,2-dithiole-3-thiones react with compounds containing an activated methyl group such as 1-methyl-3,4-dihydropyrrolo[1,2-a]pyrazine and 2-methylpyridines to furnish substituted 1,2-dithiol-3-ylidenes.