I. E. Chlenov

Synthesis of ammonium salts ofO-substitutedN-nitrohydroxylamines

Ammonium salts ofO-substitutedN-nitrohydroxylamines were synthesized by nitration ofO-substitutedN-benzoyl- orp-nitrobenzoy1hydroxylamines followed by treatment of the reaction products with an alcohol solution of ammonia.

Synthesis of potassium salts ofO-substitutedN-nitrohydroxylamines

Potassium salts of O-substitutedN-nitrohydroxylamines were synthesized by nitration of O-substituted.N-acetylhydroxylamines followed by treatment of the reaction products with potassium methoxide.

SULFONYLDIAZENE-N-OXIDES

Sulfonyldiazene-N-oxides2 and3 were obtained by treatment of sulfamide with nitroso compounds1 in the presence of 1,3-dibromoisocyanurate (DBI) in neutral and acid media.

Reaction of N-sulfonylimines with methylenediamines

N-Sulfonylimines react with N-alkyl derivatives of linear and cyclic methylenediamines with insertion into the C-N bond and formation of the corresponding dialkylaminomethyltrialkylsulfonyldiamides and trialkyl-substituted 1,2,4,6-thiatriazacyclohexane 1,1-dioxides.

Nucleophilic substitution of nitro group in 6-nitro-2,9-dioxa-1-azabicyclo[4.3.0]nonane series

Conclusions1.2,9-Dioxa-1-azabicyclo[4.3.0]nonane derivatives can exist in a conformation with a trans coupling of the rings.2.A trans coupling of the rings is realized in the primary nucleophilic substitution products of the nitro group in the 6-nitro-2,9-dioxa-1-azabicyclo[4.3.0]nonane series, which, via a conformation transformation, changes to cis coupling.

Alkylation of salts ofN-nitrohydroxylamines with chloromethylnitramines

The reactions of Ag-salts ofN-nitmhydroxyumines withN-methyl-N-chloromethylnitramine afford mainly products ofO-alkylation, whereas the reactions of the corresponding Li-, Na-, K-, Mg-, and NH4-sals in the presence of tetrabutylammonium (TBAB) give mainly products ofN-alkylation. The reactions of the corresponding. NH4-salts with bis-(chloromethyl)nitramine in the presence of TBAB lead solely to products ofO-alkylation. Increasing in the amount of TBAB results in the appearance of theN-isomer.

Preparation ofN-nitrohydroxylamines by substitutive nitration

Interaction of Na- or K-salts ofN-acetyl-N-methylhydroxylamines with aryl or aryl halides results in correspondingO-substitutedN-acetyl-N-methylhydroxylamines. Nitration of these compounds by nitronium salts or dinitrogen pentoxide results inO-substitutedN-methyl-N-nitrohydroxylamines.

Preparation ofN-nitrohydroxylamines by direct nitration

The possibilities for stabilization of compounds with the A-B-NO2 fragment, where A is an atom containing a lone electron pair, were examined. It was shown thatN-methyl-O-2,4-dinitro- and 2,4,6-trinitrophenylhydroxylamines undergo nitration with nitronium tetrafluoroborate or with a mixture of nitric acid and acetic anhydride to give the correspondingN-nitrohydroxylamines in high yields.N-Nitro-2,4-dinitrohydroxylamine that contains no methyl group at the nitrogen atom is unstable and forms a product ofO-alkylation upon reaction with diazomethane.

Cleavage of nitro group in 6-nitro-2,9-dioxa-1-azabicyclo-[4.3.0] nonane derivatives

Conclusions1.6-Nitro-8-phenyl-2,9-dioxa-1-azabicyclo[4.3.0]nonane in DMF and DMSO changes to the corresponding 6-nitrite, with prior dissociation of the C-NO2 bond.2.Cleavage of the nitro group is preceded by conformation transition, which includes inversion of the N atom.

Rearrangements in the 6-nitro-2,9-dioxa-1-azabicyclo[4.3.0]nonane series

1. 8-Substituted 6-nitro-2,9-dioxa-1-azabicyclo[4.3.0]nonanes have been rearranged to form 3-substituted spiro[isoxazoline-5,2′-tetrahydrofurans]. 2. 8-Phenyl-6-nitro-2,9-dioxa-1-azabicyclo[4.3.0]nonane has been rearranged to form 3-phenyl-5-hydroxy-5-(γ-hydroxypropyl)isoxazoline, which is converted under the action of nitrous acid into 3-phenyl-5-(γ-hydroxypropyl)isoxazole and spiro[3-phenylisoxazoline-5,2′-tetrahydrofuran].