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The complexation of chitosan and anionic surfactant, sodium dodecyl sulfate (DDS), in aqueous-alcohol media with a variable content of an organic cosolvent (methanol, ethanol, and propan-1-ol) was studied. A complicated effect of the composition of mixed solvents on the binding parameters of DDS by chitosan was observed. The introduction of 10–20 vol.% ethanol and propan-1-ol is accompanied by an increase in the degree of cooperative binding of DDS compared to that found in an aqueous solution, which leads to a decrease in the critical concentration of association and an increase in the cooperativity parameters.

Reaction of substituted 3-azido 1,4-benzodiazepine with tricyclohexylphosphine is not the Staudinger reaction and unexpectedly results in P-ylide of 1,4-benzodiazepine. This is the first example of organic azides exhibiting the pseudo halide properties in the reactions of trivalent phosphorus compounds.

The reaction of diphenylphosphorylacetonitrile with bis(dimethylamino)methane gave 2,4-bis(diphenylphosphoryl)glutaronitrile. Its rac form was obtained by the synthesis followed by crystallization. However, the reaction of the latter with bases or acids in solution yielded the meso diastereomer.

Reactions of dimethyl malonate, diphenyl malonate, methyl cyanoacetate, and malononitrile with 1-chloro-2,4,6-trinitrobenzene or 1-fluoro-2,4,6-trinitrobenzene in the presence of triethylamine in organic solvents gave stable brightly colored crystalline triethylammonium salts of the corresponding 2,4,6-trinitrophenylmalonic acid derivatives.

Depending on the reaction conditions, the reaction of 5,7-dimethyl-2-trifluoromethyl-8-azachromone with hydrogen sulfide afforded cyclic and linear dimers with the S-S bond. The regio- and stereochemistry of the reaction products were determined by 1H and 13C NMR spectroscopy.

Condensation of 4-acetyl-5-hydroxy-3-methyl-1-phenylpyrazole with RFCO2Et (RF = CF2H, CF3) in the presence of LiH affords 4-di(tri)fluoroacetoacetyl-5-hydroxy-3-methyl-1-phenylpyrazoles from which 6-di(tri)fluoromethyl-and 5-di(tri)fluoroacetyl-3-methyl-1-phenylpyrano[2,3-c]pyrazol-4(1H)-ones were synthesized. The reactions of pyrano-pyrazoles with hydrazine hydrate, ethyl mercaptoacetate, or aromatic amines proceed at the C(6) atom with pyrone ring opening and formation of aminoenones, pyrazoles, or thiophenes with the 5-hydroxy-3-methyl-1-phenyl-4-pyrazolyl fragment.

Concentration boundaries within which polymer—colloid structures exist in a sodium dodecyl sulfate—polyethyleneimine—water system were determined. The catalytic effect of this composition was found for the hydrolysis of phosphonic acid esters. The found acceleration of hydrolysis up to 25-fold is caused by reagent concentrating in a catalytic complex.

The state-of-the-art of transition of the chemical sector producing ozone-depleting substances (ODS) in Russia to non-ozone-depleting substances (NODS) is considered. The review summarizes the studies conducted by the Russian Scientific Center “Applied Chemistry” (St. Petersburg) and a number of Russian Academy Institutes including substantiation for the production methods of non-ozone-depleting hydrofluorocarbons; the most probable chemical mechanisms of their synthesis; the basis for standard process flow diagrams to be used in their full-scale manufacture; and the information on actual and newly created NODS production facilities in the Russian Federation.

On treatment with ammonia, primary amines, and pyrrolidine, 5,7-dimethyl-2-trifluoromethyl-8-azachromone undergoes ring opening to give β-aminovinyl ketones. The reactions with morpholine and piperidine proceed as addition to give 2-morpholino- and 2-piperidino-8-azachromanones. With ethylenediamine, diethylenetriamines, hydrazine hydrate, and hydroxylamine, this compound reacts similarly to 2-polyfluoroalkylchromones, yielding CF3-containing dihydrodiazepines, pyrazoles, and isoxazoles with a 2-pyridone substituent.

The reaction of 2-hydroxy-2-polyfluoroalkylchroman-4-ones with hydrazine affords 5-hydroxy-3-(2-hydroxyaryl)-5-polyfluoroalkyl-Δ2-pyrazolines, whereas 2-polyfluoroalkylchromones under similar conditions produce 3(5)-(2-hydroxyaryl)-5(3)-polyfluoroalkylpyrazoles. 5-(2-Hydroxyaryl)-1-methyl-3-polyfluoroalkylpyrazoles were synthesized in the reaction with methylhydrazine, and the reaction with phenylhydrazine afforded regioisomeric 3(5)-(2-hydroxyphenyl)-1-phenyl-5(3)-polyfluoroalkylpyrazoles.

When heated in piperidine, 1-amino-2-(3-hydroxyalk-1-ynyl)-9,10-anthraquinones undergo cyclization into 2-(1-hydroxyalkyl)naphtho[2,3-g]indole-6,11-diones. In contrast, 1-amino-2-(3-hydroxy-3-phenylpropynyl)-9,10-anthraquinone reacts with primary and secondary amines to give the corresponding 1-amino-2-(1-amino-2-benzoylvinyl)-9,10-anthraquinones, which undergo cyclization into 4-dialkylamino- or 4-alkylamino-2-phenylnaphtho[2,3-h]quinoline-7,12-diones. Heating of the starting phenylpropynol with Et3N causes its dehydrogenation and isomerization.

The addition of secondary and primary amines to ethyl (1-amino-9,10-anthraquinon-2-yl)propynoate affords an easily separable mixture of the corresponding ethyl 3-dialkylaminoor 3-alkylamino-3-(1-amino-9,10-anthraquinon-2-yl)acrylate and 3-dialkylamino- or 3-alkylaminonaphthol[2,3-h]quinoline-2(1H), 7,12-trione (in ∼4: 1 ratio). Intramolecular cyclization of the resulting substituted ethyl acrylates results in the formation of 4-dialkylaminoor 4-alkylamino-2-chlorinated pyridine rings. Subsequent nucleophilic substitution of the chlorine atom gives 2-functionalized 4-dialkylamino- or 4-alkylaminonaphtho[2,3-h]quinoline-7,12-diones.