Polyfunctional Organic Compounds Research Articles

Organic synthesis in flow mode by selective liquid-phase hydrogenation over heterogeneous non-noble metal catalysts.

Flow hydrogenation performed over heterogeneous catalysts makes organic synthesis more economical, safe and environmentally friendly. Over the past two decades, a significant amount of research with a major focus on noble metal catalysts has been carried out in this area. However, catalysts based on non-noble metals (Ni, Cu, Co, etc.) are more promising for practical use due to their low cost and high availability. This review article discusses the use of supported and bulk non-noble metal catalysts for the liquid-phase hydrogenation of bi- and polyfunctional organic compounds in flow mode. The main attention is paid to the selective reduction of one functional group (NO2, CC, CN, CO, and CN) in the presence of other substituents. In addition, cascade synthetic protocols involving hydrogenation are presented.

Catalytic synthesis of N-substituted allylarylamines

Some N-substituted allylarylamines, for example, N-(1-methyl-2-butenyl) aniline (N-MBA) form, upon isomerization, not only ortho-, but also para- and 2,6-disubstituted derivatives, which does not fit into generally accepted theory. The amino-Claisen rearrangement (ACR) of N-MBA is catalyzed by Lewis acids, cationites, and arylamine hydrochlorides. This work presents the results of studies of ACR N-MBA in solutions of mineral acids. It was found that the reaction must be carried out in dilute solutions. At H2SO4 concentrations of 0.5 mol/L and below, three parallel reactions are observed with the formation of aniline, 2-(1-methyl-2-butenyl) aniline (2-MBA) and 4-(1-methyl-2-butenyl) aniline (4-MBA). The main product in all cases is 2-MBA, the content of which in the reaction mixture exceeds the amount of 4-MBA and aniline by 7 times, which are formed in approximately equal amounts. Prolonged refluxing of 2-MBA under the reaction conditions does not lead to its isomerization to 4-MBA, i.e., the para-isomer is formed directly from N-MBA. The formation of 2,6-di-(1-methyl-2-butenyl) aniline (DMBA) was not observed. In the presence of palladium catalysts, 2-MBA cyclizes to 2,4-methyl quinoline, which indicates the ortho-arrangement of its substituents; 4-MBA does not cyclize under these conditions. The obtained compounds are of interest in the synthesis of nitrogen-containing heterocycles and other polyfunctional organic compounds.

THEORETICAL AND EXPERIMENTAL APPROACHES IN THE STUDY OF ELECTROCHEMICAL AND THERMODYNAMIC PROPERTIES OF POLYFUNCTIONAL ORGANIC COMPOUNDS IN LIQUID-PHASE AND HETEROPHASE SYSTEMS

The publication reflects the experimental substantiation and fundamental development of some important ideas of the theory of the mutual influence of functional substitution in complex molecules of macrocyclic and chelating compounds on their coordination, solvation and redox properties, as well as the formation of algorithms for searching useful functions of these compounds. Researchers of the Analytical Chemistry Department of the Ivanovo State University of Chemistry and Technology have been studying the electrochemical and thermodynamic behavior of porphyrins, complexones, amino acids, peptides and the corresponding complexes with d- and f-metal ions, their influence on coordination, solvation and catalytic processes for a number of years. The results obtained together with the literature data are discussed in the review. For citation: Bazanov M.I., Berezina N.M., Gridchin S.N., Krutova O.N., Gorboletova G.G., Bychkova S.A., Lytkin A.I., Chernyavskaya N.V., Chernikov V.V., Volkov A.V. Theoretical and experimental approaches in the study of electrochemical and thermodynamic properties of polyfunctional organic compounds in liquid-phase and heterophase systems. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2023. V. 66. N 7. P. 98-110. DOI: 10.6060/ivkkt.20236607. 6839j.

Features of the Recurrent Approximation of Retention Parameters of Polyfunctional Compounds in Reversed-Phase High-Performance Liquid Chromatography

Five antitumor drugs are selected as examples of polyfunctional organic compounds to test the possibilities of approximating their retention parameters in reversed-phase high-performance liquid chromatography using recurrent relationships of the form of tR(C + ΔС) = atR(C) + b, where C is the concentration of organic modifier in the composition of the eluent (acetonitrile), ΔC = const is a constant step of its change in concentration, and a and b are coefficients calculated using the least squares method. Examples of both ideally linear dependences in all ranges of acetonitrile concentrations and deviations from linearity in different ranges of its concentrations are revealed. Discussion of the possible reasons for such deviations (both structural factors and physicochemical properties) suggests that acid–base equilibria in the eluent are not the main ones, the positions of which depend on the concentration of the organic component. The reversible formation of hydrated forms typical of compounds whose molecules contain such polar fragments as amide ‒CO–NH– and sulfonamide –SO2–NH groups, seems more likely. Recurrent approximation of the retention parameters can be considered the simplest and most obvious way to reveal the specific interactions of the test compounds with components of the eluent.

Краткий исторический очерк по химической трансформации 2,4,6-тринитротолуола

The results of works published in the open press over the past 100 years on the possibilities of converting one of the most well-known and widely used blasting explosives (EX) – 2,4,6-trinitrotoluene (TNT, TOL, TNT) into "conversion" chemical products are summarized having a diverse and commercially attractive application. Examples of the first industrial use of TNT are not given as explosives, but as inexpensive and affordable chemical raw materials for the production of components of photosensitive compositions. The reasons for the second more intensive period of development of works (late 20th – early 21st centuries) on revealing the synthetic potential of TNT are noted. The most promising areas of work are discussed: the synthesis of polyfunctional organic compounds of a carbo (hetero) cyclic structure, interesting as biologically active substances, precursors for the synthesis of pharmaceuticals, original polymers and resins, etc. The article makes assumptions about the reasons for the fact that so far TNT has not found wide practical application as an almost universal starting compound for obtaining a wide range of products of small and large-tonnage organic intesa. Using examples of the results of their own work on obtaining original, effective dyes and pigments, sorption-active compounds, structural analogues of hard-to-reach, but practically significant natural substances, the authors suggest ways of involving TNT in the practice of industrial organic synthesis.

Synthesis of Pd/C Catalysts: Approaches to Regulating the Structure of Active Sites toward Achieving High Selectivity in Hydrogenation of Organic Compounds

The methods for regulating the physicochemical and catalytic properties of Pd/C compositions by varying their synthesis conditions were reviewed. The effect of the nature of the carbon support, the composition of the palladium precursor and its reduction conditions, and the addition of a second active metal on the formation of palladium sites, their dispersion, electronic state, and catalytic properties in practically important hydrogenation reactions was demonstrated using the results obtained by the authors. These data may be useful for the development of Pd/C catalysts exhibiting high activity and selectivity in the hydrogenation reactions of polyfunctional organic compounds.

Confirmation of organic compounds hydrates formation under the reversed-phase HPLC conditions

The confirmation of the correspondence of the detected forms of analytes to their molecular structures seems to be one of the principal problems of analytical chemistry. The previous analysis of the series of drugs by reversed-phase HPLC allowed revealing that the retention regularities of the complex polyfunctional organic compounds containing sulfonamide groups -SO2-N< differ from those of other compounds. It was explained by reversible formation of their hydrate forms. To verify this proposition, three model N-substituted arylsulfon­ami­des were synthesized, namely N,N-diethyl- (I), N-allyl- (II), and N-phenyl (III). The consideration of the dependencies of these analytes net retention times (tR) in reverse-phase HPLC on the content of orga­nic solvent (C, methanol) in an eluent did not permit us to reveal any regularities or anomalies due to the non-linearity of such depen­den­cies. However, to achieve this, the recurrent appro­ximation was re­com­mended, tR(C + DC) = atR(C ) + b (*), where DC = const – con­stant varia­tions of concentration of methanol (5% in our case), а and b – coefficients calculated by Least Squares Method. If the chemical origin of the analytes at the outlet of the chromatographic column remained the same within concentration range Сmin < С < Сmax, dependencies (*) were linear with correlation coefficients R > 0.999. Yet, if additional chemical transformations of analytes took place, na­me­ly rever­sible formation of hydrates (or variations of their composition) due to the presence of water in an eluent, it led to the deviations of recurrent dependencies (*) from linea­rity. Three sulfonamides under characterization corresponded to different kinds of such deviations: non-linearity within the whole range Сmin < С < Сmax (amide I), presence of two linear dependencies instead of one (amide II), and linearity within the whole range Сmin < С < Сmax (amide III). First two cases corres­ponded to the interconver­si­on of anhydrous forms and hydrates, or (less probable) different hydrates, while the latter meant the existence of analyte in the single form (pro­ba­b­ly hydrate). Thus, the ana­ly­sis of mo­del compounds confirmed that the presence of the polar functionality -SO2-N< was just the reason of hydrate formation in water soluti­ons.

Синтез катализаторов Pd/C: подходы к регулированию структуры активных центров для достижения высокой селективности в реакциях гидрирования органических соединений

В работе проведено обобщение способов регулирования физико-химических и каталитических свойств композиций Pd/C при варьировании условий их синтеза. На примере результатов, полученных авторами, продемонстрировано влияние природы углеродного носителя, состава предшественника палладия и условий его восстановления, добавления второго активного металла на формирование палладиевых центров, их дисперсность, электронное состояние и каталитические свойства в практически важных реакциях гидрирования. Приведенные данные могут быть полезны для создания катализаторов Pd/C, обладающих высокими активностью и селективностью в реакциях гидрирования полифункциональных органических соединений.

Keto-ether and glycol-ethers in the troposphere: reactivity toward OH radicals and Cl atoms, global lifetimes, and atmospheric implications.

Rate coefficients for the gas-phase reactions of OH radicals and Cl atoms with 1-methoxy-2-propanone (1-M-2-PONE), 1-methoxy-2-propanol (1-M-2-POL), and 1-methoxy-2-butanol (1-M-2-BOL) were determined at room temperature and atmospheric pressure using a conventional relative-rate technique. The following absolute rate coefficients were derived: k 1(OH+1-M-2-PONE)=(0.64±0.13)×10-11, k 2(OH+1-M-2-BOL)=(2.19±0.23)×10-11, k 3(Cl+1-M-2-PONE=(1.07±0.24)×10-10, k 4(Cl+1-M-2-POL)=(2.28±0.21)×10-10, and k 5 (Cl+1-M-2-BOL)=(2.79±0.23)×10-10, in units of cm3molecule-1s-1. This is the first experimental determination of k 2-k 5. These rate coefficients were used to discuss the influence of the structure on the reactivity of the studied polyfunctional organic compounds. The atmospheric implications for 1-M-2-PONE, 1-M-2-POL, and 1-M-2-BOL and their reactions were investigated estimating atmospheric parameters such as lifetimes, global warming potentials, and average photochemical ozone production. The approximate nature of these values was stressed considering that the studied oxygenated volatile organic compounds are short-lived compounds for which the calculated parameters may vary depending on chemical composition, location, and season at the emission points.

Reactions of phosphorylated 2,6-di-tert-butyl-4-methylidenecyclohexa-2,5-dien-1-ones with aliphatic, aromatic, and heteroaromatic thiols

The addition of alkanethiols, benzenethiol, and hetarenethiols to phosphorylated quinomethanes afforded P,S- and N,P,S-containing polyfunctional organic compounds as potential bactericidal agents.

The effect of preparation conditions of Pd/C catalyst on its activity and selectivity in the aqueous-phase hydrogenation of 2,4,6-trinitrobenzoic acid

The effect of the nature of alkaline agent and pH value of hydrolysis of Pd(II) chloride complex into palladium polynuclear hydroxo complexes, as precursor of active component in Pd/C catalyst, on the dispersion of palladium particles supported on carbon material Sibunit was revealed. It was shown that an increase in the particle size of supported palladium enhances the specific catalytic activity in hydrogenation of 2,4,6-trinitrobenzoic acid and changes the direction of the transformation (increases the fraction of non-aromatic intermediate, cyclohexane-1,3,5-trione trioxime, in the products). The results obtained are essential for optimizing the particle size of supported palladium in selective hydrogenation of polyfunctional organic compounds.

Reactions of phenylethynyl cuprates of lanthanides with organyl halides and synthesis of the related polyfunctional compounds

Phenylethynyl cuprate complexes of lanthanides react with organyl halides RX, Ph3CX, R3SiX, and RC(O)X (X = Cl, I; R = alkyl) in tetrahydrofuran to give polyfunctional organic and hetero-organic compounds with high yield. The reaction mechanism is discussed.

Synthesis of Polyurethane Dendrimers and Transfer Properties of Dye

The polyfunctional organic compounds 2- hydroxymethyl -1,4- butanediol (trihydric alcohol) and toluene diisocyanate -2, 4- diisocyanate (TDI) were taken as the raw materials in this study. A polyurethane dendrimer was synthesized by utilizing the difference in the reaction activity of two isocyanate groups of TDI at different temperatures. The polymerization process conditions were studied. The addition polymerization of para-position NCO groups occurred at 50 °C, and that of ortho NCO groups occurred at 90 °C. According to the structure of the dendrimer synthesized, methyl orange was used as the guest molecule. Consequently, the aqueous methyl orange showed a phase transfer. With the increase of dendrimer concentration, the transfer rate of methyl orange increased.

Preparation, Characterization, and Postsynthetic Modification of Metal−Organic Frameworks: Synthetic Experiments for an Undergraduate Laboratory Course in Inorganic Chemistry

Metal−organic frameworks (MOFs) are crystalline materials that are composed of an infinite array of metal nodes (single ions or clusters) linked to one another by polyfunctional organic compounds. Because of their extraordinary surface areas and high degree of control over the physical and chemical properties, these materials have received much attention in the recent literature for industrial applications, such as gas storage. As the applications of MOFs are significant, the underlying concepts for their design and synthesis may be used in the upper-level undergraduate laboratory as a vehicle for promoting student understanding of a wide variety of chemical concepts. These include targeted synthesis, crystallography, and adsorption theory of gases. This laboratory experiment involves the synthesis and full characterization of three MOFs that are derived from inexpensive materials, followed by surface area calculations, and in the case of one material, postsynthetic modification. Owing to the high focus on solid-state characterization, we believe this course will also provide students with a foundation in characterization methods they would not normally encounter in a typical inorganic chemistry laboratory course.

Terbium extraction in the presence of polyfunctional organic compounds and the composition of the extract pyrolysis products

Terbium extraction with benzene solutions of acetylacetone, bipyridine, and diphenylguanidine and their mixtures from aqueous chloride solutions, in particular, in the presence of tris(hydroxymethyl)aminomethane was studied. On the basis of terbium distribution in extraction systems in combination with IR and luminescence spectroscopy data for the extracts, the complexation of terbium with these ligands was discussed. The composition of the products of the pyrolysis of extracts was studied. It was shown that pyrolysis of saturated extracts can give nano-sized bulk samples and films on a quartz substrate for both terbium oxide and terbium and manganese mixed oxides.

Quantitative Structure−Property Relationship (QSPR) Prediction of Solvation Gibbs Energy of Bifunctional Compounds by Recursive Neural Networks

In this paper we apply a recursive neural network (RNN) model to the prediction of the standard Gibbs energy of solvation in water of mono- and polyfunctional organic compounds. The proposed model is able to directly take as input a structured representation of the molecule and to model a direct and adaptive relationship between the molecular structure and the target property. A data set of 339 mono- and polyfunctional acyclic compounds including alkanes, alkenes, alkynes, alcohols, ethers, thiols, thioethers, aldehydes, ketones, carboxylic acids, esters, amines, amides, haloalkanes, nitriles, and nitroalkanes was considered. As a result of the statistical analysis, we obtained for the predictive capability estimated on a test set of molecules a mean absolute residual of about 1 kJ·mol−1 and a standard deviation of 1.8 kJ·mol−1. This results is quite satisfactory by considering the intrinsic difficulty of predicting solvation properties in water of compounds containing more than one functional group.

Gas-chromatographic identification of fluorine-containing organic compounds

The gas-chromatographic retention of a series of fluoroalkylarenes on the standard nonpolar polydimethylsiloxane stationary phase OV-101 was characterized, and the retention indices of these compounds were determined. It was found that large negative values of the homological increments of these constants can serve as a sign of fluorine derivatives that contain no less than three fluorine atoms per molecule. The retention indices on polar inorganic sorbents, the silica gels Silipor 75 and Silipor 600, were chosen as the second chromatographic parameter. On these sorbents (unlike partition separation), the nonadditivity effect of the retention indices of polyfunctional organic compounds with respect to their simpler structural analogs was found for the first time. It was found that a mutual correlation between indices for this combination of a phase and a sorbent was lower than that for the combinations of phases with different polarities; this fact is responsible for the higher information content of this combination for the identification of compounds from this class.

Extraction of europium from nitrate solutions in the presence of polyfunctional organic compounds

The extraction of europium with benzene solutions of tributyl phosphate (TBP), benzoic acid (BA), and acetylacetone (AA) from nitrate solutions has been studied in the presence of the following polyfunctional organic compounds: acrylamide (AAm), phenanthroline (Phen), Diacetam-5, and Tinuvin-622. Europium distribution data in combination with luminescence spectroscopy of extracts are used to discuss europium complexing with the specified ligands. A feasibility of manufacturing Eu2O3 and EuPO4 films on quartz through the pyrolysis of saturated extracts is demonstrated.

The IUPAC Rules for Naming Organic Molecules

A systematic approach to naming polyfunctional organic compounds is presented. Latest IUPAC rules are incorporated and the table of order of precedence for the major functional groups is assembled. The scope of nomenclature is limited to common functional groups that are covered by undergraduate courses in colleges and universities.

Superelectrophilic Activation of Polyfunctional Organic Compounds Using Zeolites and Other Solid Acids.

AbstractFor Abstract see ChemInform Abstract in Full Text.