V. Yu. Orlov

Organic chemistry. History and mutual relations of universities of Russia

The review describes the history of development of organic chemistry in higher schools of Russia over a period of 170 years, since the emergence of organic chemistry in our country till now.

Synthesis of nitroacridinones from 2,1-benzisoxazole derivatives

Reaction of 3-aryl-2,1-benzisoxazoles with concentrated nitric acid in chloroform in one stage led to their conversion into acridinone nitro derivatives.

Nucleophilic Replacement of Hydrogen in para-Substituted Nitrobenzenes by Phenylacetonitrile Carbanion

The kinetic relations holding in nucleophilic replacement of hydrogen in para-substituted nitrobenzenes by phenylacetonitrile carbanion suggest a complex reaction mechanism involving two alternative pathways. The direction of the process is determined by the structure of intermediate σ-complex.

Modern Trends of Organic Chemistry in Russian Universities

This review is devoted to the scientific achievements of the departments of organic chemistry in higher schools of Russia within the past decade.

Mechanism of formation of 2,1-benzisoxazoles in reactions of nitroarenes with arylacetonitriles

Main regularities in reactions of arylacetonitriles with nitroarenes were discussed. The reaction mechanism has been suggested proceeding from the experimental data and the quantum chemical modeling of the limiting stage, the formation of the 2,1-benzisoxazole ring.

The effect of O -nucleophiles structure on the features of halogen substitution in heterogeneous systems

The formation of diphenyl ether derivatives during interaction of 4-nitrochlorobenzene and substituted phenols in a heterogeneous system [DMF in the presence of potassium carbonate and iron(III) oxide] has been studied.

Kinetics of the Reactions of 4-Nitrochlorobenzene with Substituted Phenolates in an Aprotic Polar Solvent

The kinetics of 4-nitrochlorobenzene reactions with substituted phenolates in the medium of N,N-dimethylacetamide was studied. The BrØnsted relation is fulfilled by substituted potassium phenolates: the nucleophilicity of phenolates increases with an increase in their basicity. The rate-limiting step in the reactions of 4-nitrochlorobenzene with substituted phenolates and potassium resorcinate is changed from the phenoxide anion to the phenoxide dianion. In the latter case, electron transfer from the resorcinate dianion with the generation of radical species can be responsible for the reaction rate.

Kinetics of the Reactions of 4-Nitrochlorobenzene with Substituted Phenols in the Presence of Potassium Carbonate

The kinetics of 4-nitrochlorobenzene (4-NCB) reactions with substituted phenols in the presence of potassium carbonate in N,N-dimethylacetamide was studied. Depending substituents, the reactivity of the phenols is changed in the series 3-NO2> 4-Cl > H > 4-Br > 3-CH3> 3-NH2, which is consistent with the series of their acidity. The reaction rates satisfactorily correlate with the pKavalues of the corresponding substituted phenols. Based on kinetic data (first-order and zero-order reactions with respect to phenol and 4-NCB, respectively, and the consistency of the reactivity and acidity of substituted phenols), the deprotonation of phenols is considered as the rate-determining step of the overall reaction under the test conditions. A reaction scheme was proposed for the synthesis of diaryl ethers in the presence of potassium carbonate. It involves a heterogeneous step of phenol deprotonation, which takes place on the surface of potassium carbonate, and a homogeneous step of the interaction of potassium phenolates with 4-NCB. Under the reaction conditions, the resulting bicarbonate decomposes with the formation of potassium carbonate and with the release of carbon dioxide and water.

The effect of hematite parameters on the regularities of reaction between 4-nitrochlorobenzene and substituted phenols in the presence of potassium carbonate

The formation of diphenyl ethers in the reaction between nitrochlorobenzene and phenoxide anions taking into account iron(III) oxide additives that were prepared by different methods and, consequently, have different substructures has been studied. The effect of hematite past history and its surface texture on the reaction rate has been considered. Based on the data obtained, we assumed that the effect of additives on the process under study consists in migration of potassium ions to the surface and bulk of hematite to form vacancies in the lattice of potassium carbonate, which are quite labile structural elements that possess strongly basic properties. Under the process conditions, these vacancies are the centers of the reaction with phenols.

Effect of the electronic structure of the radical anions of 4-substituted 1,2- and 1,3-dinitrobenzenes on the regioselectivity of reduction of the nitro groups

Theoretical and experimental regularities of the regioselectivity of the reduction of one of the two nitro groups in unsymmetrical dinitrobenzenes were studied. It was found that the regioselectivity of the formation of isomeric nitroanilines depends on the structure of the substrate and the nature of the reducing agent. The reduction regioselectivity model was verified, according to which radical anion protonation is the major reaction direction.