L. I. Khmel'nitskii

Nitration of imidazoles with various nitrating agents

The nitration of imidazole and its derivatives has been studied. The action of sulfuric-nitric nitrating mixture on imidazole and its nitro derivatives has given di- and trinitroimidazoles. The action of a mixture of nitric acid and acetic anhydride on the mononitroimidazoles has given the corresponding N-nitro derivatives, and some of their properties have been studied.

1,2,5-oxadiazoles substituted at ring nitrogen. part 1. synthesis and study of 2-ethyl-1,2,5-oxadiazol-3(2H)-ones.

Abstract The first representatives of the 2-alkyl-1,2,5-oxadiazol-3(2H)-ones have been synthesized by the alkylation of trimethylsilyl derivatives of 3-hydroxyfurazans using triethyl orthoformate. The compounds obtained are investigated by 13C,14N,15N and 17O NMR, MS, IR and UV.

Synthesis and reactivity of furazanyl- and furoxanyldiazonium salts

Diazotization of aminofurazans (1) and 4-aminofuroxans (2) with nitrosylsulfuric acid in a mixture of conc. H2SO4 and H3PO4 has been studied and offered as a general method for preparing furazanyl- (3) and furoxanyldiazonium (4) salts. It has been shown that reactions with the retention of the N-N-group (azo coupling, formation of triazenes and azides) are typical of salts3 and4, while elimination of the N2 molecule (Sandmeyer reaction, hydrolysis, reduction) is not typical.

Use of potassium sulfamate in the synthesis of heterocyclic nitramines

A preparative method for the synthesis of heterocyclic nitramines, containing the methylene tetramine fragment, has been proposed. The method is based on the nitration of the condensation products of urea, guanidine, 3, 4diaminofurazan, and S-aminotetrazole with formaldehyde and potassium sulfamate.

New method for the synthesis of 1,2,3-triazole 1-oxides

A general method is proposed for the synthesis of 1,2,3-triazole 1-oxides using 3,4-dinitro- or 4-amino-3-nitrofuroxanes.

Reactions of 2,4-Disubstituted 5-Nitro-1,2,3-triazole 1-Oxides. 4. Dealkylation of 2-Substituted 4,5-Dinitro-1,2,3-triazole 1-Oxides

The N-dealkylation of 2-alkyl or 2-benzyl-substituted 4,5-dinitro-1,2,3-triazole 1-oxides has been studied. Conditions have been found for N-de-tert-butylation and 4-amino-5-nitro-1,2,3-triazole 1-oxide has been synthesized for the first time.

The role of pH in the synthesis of diaziridines: 2. The effect of pH on the synthesis of diaziridines from amines, carbonyl compounds and NaOCl

In the synthesis of diaziridines from amines, carbonyl compounds, and NaOCl in water, the yields of 1,2-dialkyldiaziridines and of 1,2,3-trisubstituted diaziridines prepared from amines with electron-withdrawing substituents in the side chain are less sensitive to changes in pH than the yields of 1,2,3-trialkyldiaziridines with simple alkyl substituents. The formation of 1,5-diazabicyclo[3.1.0]hexanes is insensitive to the pH in 6.5–13.0 range. This difference is explained by the occurrence of two competing pathways to the key intermediate,N-chloroaminal.

The nitration of iodoimidazoles

Treatment of iodoimidazoles with nitric acid of various concentrations results in replacement of the iodine atoms by nitro groups, including those in the 2-position, which is not activated towards electrophilic substitution in acid media. The use of a nitric acid- sulfuric acid nitrating mixture also results in the replacements of the iodine atom in the 4(5)position.

α-hydroaxyalkyl(benzyl)furozans and α-hydroxyalkyl(benzyl)furoxans synthesis and reactivity

A general and simple preparative method for the synthesis of α-hydroxyalky(benzyl)furazan and -furoxan derivatives is proposed, The method involves reduction of acyl or ethoxycarbonyl substituents in these heterocyclic compounds with NaBH4 in ethanol. Based on the alcohols thus prepared, a number of previously unknown functional derivatives (α-nitroxyalkyl-α-haloalkyl-, and α-azidoalkylfurazans and -furoxans) have been synthesized.

Sulfamic acid andN-alkylsulfamates in the synthesis of nitro derivatives of guanidine and aminofurazan

TheN-nitro derivatives of the products of the condensation of formaldehyde with sulfamic acid derivatives and guanidine, nitroguanidine, 3,4-diaminofurazan, and 3-amino-4-methylfurazan have been synthesized.